Develop Bugs

single vs. dual SIM

i got a Mot Z Play from Amazon.de.
Unfortunately it is a "single"-SIM version. Is it possible to get DUAL-SIM functionality applying a specific firmware? Or is it hardware dependend, too. The SIM-slider has a glued dummy which can be removed.

I would say it' the same then the X play. Maybe you need only remove the glue

wolf333at said:
i got a Mot Z Play from Amazon.de.
Unfortunately it is a "single"-SIM version. Is it possible to get DUAL-SIM functionality applying a specific firmware? Or is it hardware dependend, too. The SIM-slider has a glued dummy which can be removed.
Click to expand...
Click to collapse
I removed the plastic thing on mine and installed a sim on there, my phone did nothing. I'm almost sure its just firmware, if you look down in the hole theres pins for both sims

Also would like to know whether it's HW limitation or SW(like the moto x play), I'm using a dual sim phone so this is a must for me.

sorry for over topic
is "single sim" xplay from amazon can make 2nd sim work by flashing ds firmware?
thanks

ilovemeow said:
sorry for over topic
is "single sim" xplay from amazon can make 2nd sim work by flashing ds firmware?
thanks
Click to expand...
Click to collapse
Yes it's been proven and done by many people, just search in the Moto X Play forum. This is the Moto Z Play forum.

Where did you put the 2nd sim in? In the micro SD slot?
Sent from my D6503 using XDA-Developers mobile app

paulwollf said:
Where did you put the 2nd sim in? In the micro SD slot?
Click to expand...
Click to collapse
If you have a dual SIM version, then obviously you put it in the 2nd SIM slot.
If you have a single sim version, there is nothing you can do right now to use 2nd SIM. There might be a way in the future to convert single SIM version to dual SIM by flashing dual SIM ROM, but that's not guaranteed. If it's possible, you also need to remove the plastic that's blocking the 2nd SIM slot.

Or I'm sure someone will make cyanogenmod for the z play and enable dual sim
Sent from my D6503 using XDA-Developers mobile app

paulwollf said:
Or I'm sure someone will make cyanogenmod for the z play and enable dual sim
Click to expand...
Click to collapse
It's not just a software thing, for this to work, the hardware needs to have an IMEI for the 2nd SIM slot (but 2nd SIM slot is disabled in the ROM and also physically blocked by the plastic). If the phone doesn't have a 2nd IMEI, it won't work regardless of what you do with the software.

What would that mean? A dual sim firmware would enable a 2nd imei? Other than that you can let the sim part print by a 3d printer there are shops in my town which do that
Sent from my D6503 using XDA-Developers mobile app

paulwollf said:
What would that mean? A dual sim firmware would enable a 2nd imei? Other than that you can let the sim part print by a 3d printer there are shops in my town which do that
Click to expand...
Click to collapse
A Dual SIM firmware will not enable a 2nd IMEI, IMEI is assigned to the hardware, there is nothing you can do in software that can add an IMEI. If 2nd IMEI is not present the firmware will see it as all zeros, and most likely cannot use the 2nd SIM, A Dual SIM firmware will allow you to use the 2nd SIM slot IF there is a 2nd IMEI.
I"m not sure what you mean by your second sentence, what's a SIM part?

I mean that you could let a 3d printer create a sim tray with a hole for the second sim
Sent from my D6503 using XDA-Developers mobile app

paulwollf said:
I mean that you could let a 3d printer create a sim tray with a hole for the second sim
Click to expand...
Click to collapse
You definitely can, but it's probably easier and definitely cheaper to remove that piece of plastic. A lot of people have done it.

hjk23 said:
A Dual SIM firmware will not enable a 2nd IMEI, IMEI is assigned to the hardware, there is nothing you can do in software that can add an IMEI. If 2nd IMEI is not present the firmware will see it as all zeros, and most likely cannot use the 2nd SIM, A Dual SIM firmware will allow you to use the 2nd SIM slot IF there is a 2nd IMEI.
I"m not sure what you mean by your second sentence, what's a SIM part?
Click to expand...
Click to collapse
That you cannot change or assign an IMEI is just not true. It´s not legal and so on but there are Xposed modules that let you do it for example. With MTK-Devices it would even be just an command in engineers mode, for wich you don´t even need root (Done that many times). With Qualcomm devices its a bit more difficult, but still managable (step-by-steps can be found via Google)

Yogurthluder said:
That you cannot change or assign an IMEI is just not true. It´s not legal and so on but there are Xposed modules that let you do it for example. With MTK-Devices it would even be just an command in engineers mode, for wich you don´t even need root (Done that many times). With Qualcomm devices its a bit more difficult, but still managable (step-by-steps can be found via Google)
Click to expand...
Click to collapse
There is so much wrong with this post, I don't even know where to start.
"It´s not legal" - if something is legal or illegal is always based on your jurisdiction. The vast amount of countries and states have no law against modifying one's IMEI. Hence, there is absolutely nothing "illegal" about it. There are a few notable exceptions, those are mostly the countries that won't let you use a device with a blank IMEI in the first place (like the UK).
"there are Xposed modules that let you do it for example"
Please, point us to one that works with a current or even semi-current Qualcomm SoC. Given that the IMEI is controlled by the baseband it sounds exceptionally unlikely that they actually change the IMEI that is broadcast to the cellular provider.
"With Qualcomm devices its a bit more difficult, but still managable"
Again, please give us a source for such instructions for a current or even semi-current Qualcomm SoC.
There is a reason why nobody ever found a way to change the IMEI on the X series dual sim mods. This is unlikely to change with the new Z series.

freibooter said:
There is so much wrong with this post, I don't even know where to start.
"It´s not legal" - if something is legal or illegal is always based on your jurisdiction. The vast amount of countries and states have no law against modifying one's IMEI. Hence, there is absolutely nothing "illegal" about it. There are a few notable exceptions, those are mostly the countries that won't let you use a device with a blank IMEI in the first place (like the UK).
"there are Xposed modules that let you do it for example"
Please, point us to one that works with a current or even semi-current Qualcomm SoC. Given that the IMEI is controlled by the baseband it sounds exceptionally unlikely that they actually change the IMEI that is broadcast to the cellular provider.
"With Qualcomm devices its a bit more difficult, but still managable"
Again, please give us a source for such instructions for a current or even semi-current Qualcomm SoC.
There is a reason why nobody ever found a way to change the IMEI on the X series dual sim mods. This is unlikely to change with the new Z series.
Click to expand...
Click to collapse
Hi,
okay, i´ll be honest with you: I havn´t done that on any Qualcomm device since maybe 2 years. Maybe you are right, maybe not. After about 15 sec Google-work I found many posts like this one:
http://www.androidbrick.com/ultimat...agon-xiaomi-mi5-imei-and-baseband-repair-fix/
They are talking about the 820, so I guess thats "current" enough Might be, that Lenovo did some stuff to prevent this, but obviously its not totally false to assume, that with some (most, many) Qualcomm devices you can still get/change the IMEI.
Sure there are always exeptions from the rule (with Gionee M5 Plus I wasn´t even be able to enter fastboot lol), but to say, that an IMEI is assigned to the hardware is at least as false as my - maybe to hasty submitted - reply.
About the "legal"-thingy: Yeah, sorry for not thinking about that. All regions I ever where it was illegal (UK, GER etc). But I guess, thats not to important here

Is it possible to use two SIMs on a single SIM S9+

Evil Samsung does not sell dual sim models in Australia... Is there a way to use two sims in their single sim phones? Was this ever possible with S7 and S8 phones?
I have an international model S7 edge but decided to get an Australian S9+ because they receive better service and support here, well, actually I broke the screen of that S7 edge, again, and the repairing cost by a 3rd party just made it pointless, all because Samsung Australia won't repair it for me (for a more reasonable A$210) for it is an international model (UAE).
If this is technically possible, best case scenario I just need to find a correct SIM tray?

You can use two different SIMs if the phone is not locked to a particular network.
However, if the phone is not Dual SIM, you will not manage to use both cards at the same time.

RossTeagan said:
You can use two different SIMs if the phone is not locked to a particular network.
However, if the phone is not Dual SIM, you will not manage to use both cards at the same time.
Click to expand...
Click to collapse
So you are saying the hardware is there, but the software won't allow me to use both SIMs at the same time?
I take it as flashing dual SIM ROM would not only void warranty, but beats the purpose of buying an authentic local market device in the first place?

sunheatyy said:
So you are saying the hardware is there, but the software won't allow me to use both SIMs at the same time?
I take it as flashing dual SIM ROM would not only void warranty, but beats the purpose of buying an authentic local market device in the first place?
Click to expand...
Click to collapse
No, what I mean is that you can use two SIM by switching them and having only one at a time inserted in the phone.
If the phone is not dual SIM, you can have two SIM cards working on it only if the phone is a Hybrid Dual SIM.
If the phone is SINGLE SIM, you can't do anything about it.
Hope that this answers your question.

Samsung S9 European Dual Sim

I've been given a GM960F S9 from work to use as my company phone.
From what I can read online there is no difference between GM960F and /FD in Europe and some phones have the mode 960F and are dual sim capable.
I managed to source a S9 Sim Dual Sim tray but when I put two sims in there only one shows up - is this a software restriction / is it possible to override and make this dual sim?
Thanks!

cono1717 said:
I've been given a GM960F S9 from work to use as my company phone.
From what I can read online there is no difference between GM960F and /FD in Europe and some phones have the mode 960F and are dual sim capable.
I managed to source a S9 Sim Dual Sim tray but when I put two sims in there only one shows up - is this a software restriction / is it possible to override and make this dual sim?
Thanks!
Click to expand...
Click to collapse
what firmware are you running? also, if you look in the last 2 or 3 pages of threads, there is talk about the dual sim having issues. Check those threads for a possible solution

youdoofus said:
what firmware are you running? also, if you look in the last 2 or 3 pages of threads, there is talk about the dual sim having issues. Check those threads for a possible solution
Click to expand...
Click to collapse
Using Baseband G960FXXU4CSE1 Build PPR1.180610.011G960FXXU4CSE3
My question concerns a phone that came with a single sim tray, is it possible to put a dual sim tray in and get the dual sim card functionality working??

cono1717 said:
Using Baseband G960FXXU4CSE1 Build PPR1.180610.011G960FXXU4CSE3
My question concerns a phone that came with a single sim tray, is it possible to put a dual sim tray in and get the dual sim card functionality working??
Click to expand...
Click to collapse
if it physically doesnt have 2 sim readers, then no. If its the g960f vs the g960f/ds then no. Do you have a dual sim card tray that you can pop in it?

youdoofus said:
if it physically doesnt have 2 sim readers, then no. If its the g960f vs the g960f/ds then no. Do you have a dual sim card tray that you can pop in it?
Click to expand...
Click to collapse
I do, I put one in there and it didn't seem to recognise the second SIM, I just wondered if there was a physical difference but I guess the difference is Hardware based then if there is no overriding it?

cono1717 said:
I do, I put one in there and it didn't seem to recognise the second SIM, I just wondered if there was a physical difference but I guess the difference is Hardware based then if there is no overriding it?
Click to expand...
Click to collapse
well, if it fit in there, that leads me to believe that it also has a reader. Have you flashed the g960f/ds firmware?

youdoofus said:
well, if it fit in there, that leads me to believe that it also has a reader. Have you flashed the g960f/ds firmware?
Click to expand...
Click to collapse
I have not - I will try flashing that and seeing if it can recognise the duo sim tray.

Oneplus Nord N10 5G hardware variants

Does anyone have the full list of hardware variants?
BE2025 - Metro, maybe t-mobile?
Be2026 - NA
BE2028 - EU?
BE2029 - Global
I bought the BE2026 straight from oneplus in the US and realized that the situation isn't quite like it is with the Oneplus 7T.
The NA model (BE2026) doesn't have the electrical contacts inside to support a second sim, even if you were to get the dual sim tray and flash to global. I'm wondering if maybe the BE2025 might have them, in which case I can flash to global rom if I buy through tmo.

Can confirm BE2025 is Metro, just got the phone from them today. As far as flashing goes, might be a no-go on the Metro variant as it looks like the Unlock Bootloader option is greyed out and off unlike my Moto G Stylus. haven't looked into it any further yet though.

When you peer inside the sim slot, do you see sim card contacts? The contacts for the "main" sim should be too far back to easily see (behind the microsd card contacts). The contacts for the second sim should be in front of the microsd card.
Also, what is build number? Then unlock thing I assume is because you need to request unlock token from Oneplus.
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Unfortunately I don’t see a second SIM contact in there. I see the first SIM contacts all the way in the back and in front of it is nothing but a flat surface. Build number is 10.5.8BE88CF

GCPDetective said:
Unfortunately I don’t see a second SIM contact in there. I see the first SIM contacts all the way in the back and in front of it is nothing but a flat surface. Build number is 10.5.8BE88CF
Click to expand...
Click to collapse
Sounds like BE2025 and BE2026 (the picture I put up is from the BE2026) are the same hardware wise. I'm guessing the dual-sim versions are the EU and international versions.
Unfortunately, I guess T-mobile and Metro are using the single-sim versions straight up with their own ROM rather than offering a dual-sim version with a single sim tray and their own ROM like they did with the OP 7T.

topofthehat said:
Sounds like BE2025 and BE2026 (the picture I put up is from the BE2026) are the same hardware wise. I'm guessing the dual-sim versions are the EU and international versions.
Unfortunately, I guess T-mobile and Metro are using the single-sim versions straight up with their own ROM rather than offering a dual-sim version with a single sim tray and their own ROM like they did with the OP 7T.
Click to expand...
Click to collapse
not all that suprising considering they also locked down the ability to qfil in an international rom as well. i got one of these from metro and im contemplating paying the 50$ or so to get it unlocked online unless someone can figure out a way to unlock the device without the metro 180 day requirement.

What do you mean? How is it locked down? It's not like the other tmo OnePlus devices where you need to request token to unlock bootloader?

Hello everyone, I pre-ordered mine from OnePlus (BE2026) got it and found out that I couldn't even find a dual sim card tray to buy, also there is a good chance that it doesn't even support dual sim plus micro sd card, if someone knows where to buy a dual sim card tray for Nord N10 5G please share the link, I still want to try it. Thanks in advance guys.

oscarmaldonado said:
Hello everyone, I pre-ordered mine from OnePlus (BE2026) got it and found out that I couldn't even find a dual sim card tray to buy, also there is a good chance that it doesn't even support dual sim plus micro sd card, if someone knows where to buy a dual sim card tray for Nord N10 5G please share the link, I still want to try it. Thanks in advance guys.
Click to expand...
Click to collapse
Wont matter even if you find one. The BE2026 doesn't have the sim contacts inside the phone to support a 2nd sim. Pretty sure only the BE2028 and BE2029 have them. I bought BE2026 from Oneplus directly. The picture of the phone lacking the second sim contacts in my second post is the BE2026 that I have on my desk right now.
Plus the BE2026 ships with the International ROM (BE86AA) on it, which means if there was second sim support it should already show up in the phone settings.
The dual sim version is a nano + nano/microsd, not a nano + nano + microsd, so the contacts have to exist right in front of the microsd card. You can see the SIM tray for the dual-sim version in this video at the 3:00 mark.
The OP 7T kind of screwed up our assumptions, because there were no physical hardware variants. So the international version was physically the same as the na version, different firmware for band support sure. The tmo version simply had t-mobile ROM to disable the second SIM for the carrier phones. When you put international ROM on them, the second sim was "unlocked." With the OP N10 5G it looks like the situation is different, there is a physical difference between the NA and EU/international version. It appears that the NA version actually has no second sim support at all, physically, so you can't just unlock (not that it matters since the BE2026 already has international ROM).

topofthehat said:
Wont matter even if you find one. The BE2026 doesn't have the sim contacts inside the phone to support a 2nd sim. Pretty sure only the BE2028 and BE2029 have them. I bought BE2026 from Oneplus directly. The picture of the phone lacking the second sim contacts in my second post is the BE2026 that I have on my desk right now.
Plus the BE2026 ships with the International ROM (BE86AA) on it, which means if there was second sim support it should already show up in the phone settings.
The dual sim version is a nano + nano/microsd, not a nano + nano + microsd, so the contacts have to exist right in front of the microsd card. You can see the SIM tray for the dual-sim version in this video at the 3:00 mark.
The OP 7T kind of screwed up our assumptions, because there were no physical hardware variants. So the international version was physically the same as the na version, different firmware for band support sure. The tmo version simply had t-mobile ROM to disable the second SIM for the carrier phones. When you put international ROM on them, the second sim was "unlocked." With the OP N10 5G it looks like the situation is different, there is a physical difference between the NA and EU/international version. It appears that the NA version actually has no second sim support at all, physically, so you can't just unlock (not that it matters since the BE2026 already has international ROM).
Click to expand...
Click to collapse
Thanks for your reply bud, I'm returning it, according to the customer service representative there is no international version of Nord N10 5G that comes with 2 sim cards and micro sd card slots ( tray). Thanks again and stay safe.

oscarmaldonado said:
Thanks for your reply bud, I'm returning it, according to the customer service representative there is no international version of Nord N10 5G that comes with 2 sim cards and micro sd card slots ( tray). Thanks again and stay safe.
Click to expand...
Click to collapse
That's not true. If you look at the difference between the US product page and UK product page for the N10 5G. (plus the video shows dual sim for N10 5G does exist). The BE2028 (UK I believe has this one) and BE2029 should come with dual sim.
US website " SIM and external memory card slot (nano-SIM + microSD) "
UK website " 3-choose-2 hybrid SIM slot (nano-SIM + nano-SIM/microSD) "
The problem is the US website has this residual bottom notation on the product page " 7. Currently supports dual 4G SIM cards or a single 5G SIM. 5G+4G suport available via OTA update at a future date. Please confirm 5G network availability with your carrier. " This made me think it was a dual sim phone with a single sim tray. In actuality, the NA version is a single sim phone with a single sim tray.
And assuming the Tmobile version is the BE2025 just like the metro version, it too would appear to be the same as the BE2026.
I would love to be wrong. If someone else has ended up purchasing a phone from Metro, T-mo, or Oneplus in the US and can peer into their sim slot and see sim contacts in front of the microsd contacts, that would be great.

topofthehat said:
That's not true. If you look at the difference between the US product page and UK product page for the N10 5G. (plus the video shows dual sim for N10 5G does exist). The BE2028 (UK I believe has this one) and BE2029 should come with dual sim.
US website " SIM and external memory card slot (nano-SIM + microSD) "
UK website " 3-choose-2 hybrid SIM slot (nano-SIM + nano-SIM/microSD) "
The problem is the US website has this residual bottom notation on the product page " 7. Currently supports dual 4G SIM cards or a single 5G SIM. 5G+4G suport available via OTA update at a future date. Please confirm 5G network availability with your carrier. " This made me think it was a dual sim phone with a single sim tray. In actuality, the NA version is a single sim phone with a single sim tray.
And assuming the Tmobile version is the BE2025 just like the metro version, it too would appear to be the same as the BE2026.
I would love to be wrong. If someone else has ended up purchasing a phone from Metro, T-mo, or Oneplus in the US and can peer into their sim slot and see sim contacts in front of the microsd contacts, that would be great.
Click to expand...
Click to collapse
Maybe it's ESIM?

GCPDetective said:
Maybe it's ESIM?
Click to expand...
Click to collapse
Can't be. Look at the video review I posted at the 3:00 mark. You can clearly see it is a nano/micro sd + nano sim tray. Notice how you can see "SIM 2" written on the sim tray. My N10 5G (BE2026) sim tray doens't have that written on it and it slightly slimmer at that part, which make sense since it can only fit a micro sd not a nano.
Only logical explanation right now is that the na version doesn't have the contacts. M

topofthehat said:
Can't be. Look at the video review I posted at the 3:00 mark. You can clearly see it is a nano/micro sd + nano sim tray. Notice how you can see "SIM 2" written on the sim tray.
Only logical explanation right now is that the na version doesn't have the contacts.
Click to expand...
Click to collapse
Only reason I mention ESIM is because of the future OTA update wording you mentioned seems like something that could be enabled via software if it's hiding in the phone. Just speculation though.

Forgot to mention that the reason that popped into my head is because Apple did the same thing with the US and China a few years ago when the iPhone X came out. Physical SIM + ESIM for US and 2 Physical SIMs for China

GCPDetective said:
Only reason I mention ESIM is because of the future OTA update wording you mentioned seems like something that could be enabled via software if it's hiding in the phone. Just speculation though.
Click to expand...
Click to collapse
Ah, i see what you mean, but atlas, that is not the case here.
It wouldn't explain the sim tray in the EU/international version.. Pretty sure the guy in the review is in the UK doing a review of the UK N10 5G. I compared this to my phone sim tray, it is a bit different. Look at yours, the BE2026 and BE2025 sim tray should be the same. You'll see what I mean.
Picture from the EU N10 5G video review:
The website notation is probably because someone in marketing was lazy and copy and pasted the NA specs from the international one. They changed the relevant information for the SIM tray in the main section but forgot to delete the fine print footnotes.

GCPDetective said:
Forgot to mention that the reason that popped into my head is because Apple did the same thing with the US and China a few years ago when the iPhone X came out. Physical SIM + ESIM for US and 2 Physical SIMs for China
Click to expand...
Click to collapse
Oh now I get the point you were trying to make. I suppose that is possible. I highly doubt it, since this is suppose to be a budget 5G. Apple and Google were more than happy to advert they were going to have esim on their phones in the future through updates (i.e. Pixel 3a).
We've heard nothing from Oneplus about esims. It would seem odd they would choose to do so starting with one of their budget phones. I could equally be wrong. However, for me, if they went esim + sim, i would still rather have 2 physical sims. (I already have a Pixel 4.) That is part of the reason I wanted (and wrongly assumed) the N10 5G in the first place; for it having 2 physical sims.
The simplier explanation would be that Oneplus is just following the convention of their competitors: NA models gets single sim, International gets dual-sim.

topofthehat said:
Does anyone have the full list of hardware variants?
BE2025 - Metro, maybe t-mobile?
...
I'm wondering if maybe the BE2025 might have them, in which case I can flash to global rom if I buy through tmo.
Click to expand...
Click to collapse
Hello. Can confirm BE2025 is a MetroPCS variant.

topofthehat said:
Does anyone have the full list of hardware variants?
BE2025 - Metro, maybe t-mobile?
Be2026 - NA
BE2028 - EU?
BE2029 - Global
I bought the BE2026 straight from oneplus in the US and realized that the situation isn't quite like it is with the Oneplus 7T.
The NA model (BE2026) doesn't have the electrical contacts inside to support a second sim, even if you were to get the dual sim tray and flash to global. I'm wondering if maybe the BE2025 might have them, in which case I can flash to global rom if I buy through tmo.
Click to expand...
Click to collapse
The BE2028 is the T-mobile US version

Wait.... So we have three hardware versions in the US? ?
BE2025 - Metro
BE2026 - Unlocked from Oneplus directly
BE2028 - T-mobile???
Can anyone else confirm that BE2028 is from T-mobile?

Question Single to dual SIM possible?

Is it possible to convert network locked single SIM models to dual SIM?

im not familiar with this, but how does that even work? There's only 1 sim slot on the single sim version, and only 2 on the dual sim version. I guess you might be able to get some sort of modification or adapter board to connect for dual sim, but that would be a bit janky wouldnt it?

PhotonIce said:
im not familiar with this, but how does that even work? There's only 1 sim slot on the single sim version, and only 2 on the dual sim version. I guess you might be able to get some sort of modification or adapter board to connect for dual sim, but that would be a bit janky wouldnt it?
Click to expand...
Click to collapse
It has a single slot in the SIM tray, yes, but I hoping the internal hardware might be the same as a dual SIM model. That might be unrealistic as I can't find a region that offers both dual SIM and NFC. What I do know is that it is possible to convert at least some Oppo models from single to dual SIM by changing the region and flashing other firmware and of course replacing the SIM tray. After that, it works like a bought one.

just sell yours and buy a dual sim model, why go through all this trouble?
it will probably cost the same, if not a little bit more, but it would be a genuine dual sim model.
most dual sim budget phones dont have nfc anyways.
i dont know any other information, so sorry for not being much of a help

Yes the phone is dual Sim variant , just need to buy dual Sim card tray or if inpatient, and a steady hand, just cut the Sim card holder for second Sim out.

Blank tape said:
It has a single slot in the SIM tray, yes, but I hoping the internal hardware might be the same as a dual SIM model. That might be unrealistic as I can't find a region that offers both dual SIM and NFC. What I do know is that it is possible to convert at least some Oppo models from single to dual SIM by changing the region and flashing other firmware and of course replacing the SIM tray. After that, it works like a bought one.
Click to expand...
Click to collapse
The Australia prepaid Optus has both dual Sim and nfc

smiley.raver said:
Yes the phone is dual Sim variant , just need to buy dual Sim card tray or if inpatient, and a steady hand, just cut the Sim card holder for second Sim out.
Click to expand...
Click to collapse
Sorry if this is a dumb question, but why the heck would they cover up a second sim slot if available? Isn't a second sim slot better for their marketing of the device? Wouldn't the device show up as dual sim in the about phone section of settings, despite only having one usabale slot? It doesn't sound like a smart thing to do.
They're also wasting that "precious" in-phone space, not to mention the manufacturing costs to make a dual sim model (which is single sim), only to sell it for the same or less than an actual dual sim model with a usable second sim slot.
Usually what they do is they remove the second slot to make room for the nfc module. That's why you don't often see dual sim phones with nfc in the budget/mid range, it's either one or the other.

Mate, completely agree, but you need to ask mtk/Oppo/realme
The only explanation I can think is, that in Australia, it is extremely rare to be able to buy dual Sim straight off the shelf, usually havego order in(from my experience abut that could also just be Sony phones as well) only my second realme and the C3 that I had before this phone was exactly same
Again, question needs to be asked off manufactures lol
I can only tell you what is and what can be done, as I modified the Sim card tray as stated and put Sim In and there you go.

Wow. I thought that they might disable dual sim since the model is a "single sim" one, despite it having the hardware capabilities.

It is disabled in Australian firmware. That is not surprising for a carrier locked model for obvious reasons but what is somewhat surprising is that the carrier unlocked Australian version which seems to be only sold online direct from realme is also the same model at the same RRP. I think it might be realme's only single SIM model sold in AU. I suspect you might lose NFC if you install dual SIM firmware on it but smiley.raver would know for sure.
I can only speculate that since Australia is a relatively small market it is not worth the effort of manufacturing a special hardware variant for it. OTOH, if that is true that suggests the model might have latent NFC characteristics in other markets which seems a bit of a stretch, so it maybe that it is harder to subtract the 2nd SIM contacts than add NFC. TBH, for such a low power CPU its a bit surprising to see NFC anyway but Optus would only care about the end result for the cheapest cost and maybe the different firmware and modified SIM tray is the cheapest manufacturing option.

As attached. Wish I had some spare tags lying around to show working but screenshot is best J can do lol

What combo of region and firmware are you using or other magic? It's interesting that the firmware you are using has auto-detected either the 2nd SIM or NFC when that combination is not sold in any region.

Blank tape said:
What combo of region and firmware are you using or other magic? It's interesting that the firmware you are using has auto-detected either the 2nd SIM or NFC when that combination is not sold in any region.
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Click to collapse
Also interested in knowing how to use a second Sim. Out of curiosity I modified the Sim tray, but the 2nd Sim was not detected. Android 11, rmx3201AU_11_C.09

If you search the Oppo threads you can find the odd guide on changing the region for example this thread I don't know whether that is sufficient and if its is whether the mix of Australian firmware and different region causes a problem with future updates. I'm lead to believe that changing the region via the process in the linked thread is not possible with Android 11 or at least after some particular update on Android 11. If changing the firmware is required I don't know whether there is a suitable image that will flash itself but there are programs that will do that e.g. mtkclient.
Hopefully, smiley.raver will comes back and provide some more pointers or maybe you will if you're braver and less patient than me.
Good luck!

Blank tape said:
If you search the Oppo threads you can find the odd guide on changing the region for example this thread I don't know whether that is sufficient and if its is whether the mix of Australian firmware and different region causes a problem with future updates. I'm lead to believe that changing the region via the process in the linked thread is not possible with Android 11 or at least after some particular update on Android 11. If changing the firmware is required I don't know whether there is a suitable image that will flash itself but there are programs that will do that e.g. mtkclient.
Hopefully, smiley.raver will comes back and provide some more pointers or maybe you will if you're braver and less patient than me.
Good luck!
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Click to collapse
Just an update, phone automatically updated with rmx3201_11_C.11 but still only detects one Sim.

It won't happen by itself. You need to change the region code and/or install firmware from another region to have the 2nd SIM detected. If you need to rollback to Android 10 so you can change the region code there is a link to a rollback package in the post introducing realme UI 2.0 / Android 11 on the (Indian) realme community site. If you can't find it let me know and I'll have a look later.

Yes you will need to roll back to adtod 10, to change region for firmware, as I said in running Australia Optus prepaid region and I get the updates as well as the dual Sim and nfc(if you need a quick way to test of nfc works use a bank card with a chip on it , turn nfc on and putghw card near the phone, phone will either do nothing or say no process to view the data or something along those lines which means it has recognised a nfc device near it.

I'm not sure I was able to parse that properly. Which region did you change to? Are you saying that you didn't reflash the Optus firmware and continue to receive updates?

Just used the region changing method, selected the Australia Optus prepaid, , phone restarts no data lost.
Done on 2 c21 phones, both have working nfc and 2nd Sim.
I will back up my other 'testing' c21 and try make short video to show it all working,
Region changing in android 11 requires god like access it seems to access that same section, there is probably a way to do it. But just easier to roll back to android 10, change region, reflash you backup, then wipe (this is only if already upgraded to 11, that there is a data loss) mdc, usereata, metadata and then you will be on working android 11, dual Sim, and nfc
I will see if I can find an old sim card, and uploaded short video with both those features working, the 2 c21 phones I have were also brought from different supply chains as well

smiley.raver said:
Just used the region changing method, selected the Australia Optus prepaid
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Click to collapse
Excuse my density, but I would have assumed that would be the region the phone ships with.
I will see if I can find an old sim card, and uploaded short video with both those features working, the 2 c21 phones I have were also brought from different supply chains as well
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Click to collapse
Don't do a video just for me. I never watch them, but I wouldn't mind reading your comments on one of the existing guides about any gotchas or steps that can be eliminated. I don't really understand what the software is doing apart from enabling the region change and possibly other codes. Would be good if there was an open source version of the tool.
BTW, according to a post on OzBargain there seem to be 2 versions or perhaps production runs of the Optus C21. The later one has a screen protector applied and there is no carrier lock. Looks like even the one realme sells directly is also (Optus?) locked as their web site changed recently to state they woud supply an unlock code with the phone.