Develop Bugs

Does US variant come with dual sim active?

My phone shipped from Amazon today and due Monday. Does anyone know if the US unlocked variant shipp with both sims (nano and eSiM) active? Need dual SIMs for work so hoping it does.

TGUY25 said:
My phone shipped from Amazon today and due Monday. Does anyone know if the US unlocked variant shipp with both sims (nano and eSiM) active? Need dual SIMs for work so hoping it does.
Click to expand...
Click to collapse
I checked Motorola's site earlier today, in the specs section, down in the fine print notes, it states Dual-Sim capabilities will be introduced at a later date & may vary depending on carrier model.
At the minimum, sounds like you may have to wait for a software update to enable Dual-Sim capabilities.

Ordered mine from Motorola yesterday and hoping it comes with dual standby. However, I checked out a T-Mobile version yesterday and although it allowed to hot-swap swap from Nano to eSIM in the software it only had one IMEI number... Hoping the unlocked version maybe different but no software update can alter the missing IMEI. Fingers crossed but honestly not hopeful.

Mine is on the UPS truck for delivery this afternoon (unlocked version bought on Amazon) - earlier than expected so I will be able to report back after I have it. I'd read the info on the motorola website mentioned above and was hoping to get a definitive answer.

I got my unlocked Razr 5G (from Amazon) today. Box only shows 1 IMEI. Pretty sweet device - just working on setup but I can report that 1) both eSIM and the Nano SIM work BUT (and this is a really big BUT), only one can be active at a time. I started with my AT&T nano SIM in the device and it works great. I then switched to the eSIM and added my UK eSIM plan to the phone.
I was then able to go back & forth between the SIMs using the switch SIM menu option and it worked fine but only one can be Active at a time so when AT&T is active, no calls, etc on UK eSIM and vice-versa.
So, while it is technically a dual SIM phone, it does not behave as you would expect (or prefer) for a true dual active-dual sim phone. Given the box only shows 1 IMEI i'm doubtful the phone will ever be dual standby (which would require 2 IMEI's) so I'm not sure if I'll be able to use this as a daily driver or not.
Mine is the US version - nXT2071-3 - hopefully someone in the UK or elsewhere with a different model/firmware can confirm if another version is true dual SIM.

TGUY25 said:
I got my unlocked Razr 5G (from Amazon) today. Box only shows 1 IMEI. Pretty sweet device - just working on setup but I can report that 1) both eSIM and the Nano SIM work BUT (and this is a really big BUT), only one can be active at a time. I started with my AT&T nano SIM in the device and it works great. I then switched to the eSIM and added my UK eSIM plan to the phone.
I was then able to go back & forth between the SIMs using the switch SIM menu option and it worked fine but only one can be Active at a time so when AT&T is active, no calls, etc on UK eSIM and vice-versa.
So, while it is technically a dual SIM phone, it does not behave as you would expect (or prefer) for a true dual active-dual sim phone. Given the box only shows 1 IMEI i'm doubtful the phone will ever be dual standby (which would require 2 IMEI's) so I'm not sure if I'll be able to use this as a daily driver or not.
Mine is the US version - nXT2071-3 - hopefully someone in the UK or elsewhere with a different model/firmware can confirm if another version is true dual SIM.
Click to expand...
Click to collapse
But... i have dual Sim smartphone, and it uses 2 nano-sims. I have them both activated and so the phone shows the two IMEI (from both carrier sims). My previous non chinese smartphone was an iPhone 11 and it had esim and a sim slot. So I used the first e-sim with my Canadian carrier and the sim card slot with my other canadian carrier. I could use both phone numbers on the same device but if one phone number rang on the phone I could not receive an inbound call on the second number.
Is that not how the Razr 5G works?

US variant (XT2071-3) that I got does not work like an iphone 11 (which i what I have now and,like you have one carrier using nano sim and another using eSIM) and both can send/receive calls and text - though like you said not at once- and it can do that because it has 2 unique IMEI and which allows it to register on 2 different networks. Moto XT2071-3 only have 1 IMEI - can only have 1 number on at a time and when one is on, the other is off - doesn't receive calls/texts when off.
EU variant XT2071-4 is supposed to come with 2 IMEI to work like your iphone 11 - both sims can be on and get calls/text. Very few have been shipped. i have one on order and will confirm when i get it. if that one works, i will keep it. The one i got from AMAZON is going to be returned since I can't use it.

I would guess that Dual SIM Dual Standby for 5G is coming with Android 11. It was the case with the OnePlus phones and perhaps that feature isn't available with Android 10. Are there any Dual SIM 5G phones with Android 10? This article helped explain the situation (along with the comments below) Android Authority Dual SIM 5G phones

kingstu said:
I would guess that Dual SIM Dual Standby for 5G is coming with Android 11.
Click to expand...
Click to collapse
Hopefully the wait for 11 isn't too long

I got a UK version XT2071-4 and can report it is a true dual sim phone. Box shows dual SIM’s and I was able to load my US ATT eSIM and my Starhub nano sim on the phone and it works. You can’t use 5G in dual sim mode - probably something about the modem but it works great in 4G LTE with both sims. The global version is missing a few US specific bands though, running on ATT, not missed very much. So far so good. While the build quality isn’t as good (more plastic) I like the smaller form factor over the z-flip and the close to vanilla Android is nice. Happy camper now with full dual sim model - the us model I got from Amazon is going back. Now I just need a decent case...

Question Dual Sim North American For OP Pro 9

The specs page says Pro 9 has dual Sim but all the press reviews say that the US Version will have only single sim. Does anyone know? If 9 Pro unlocked NA version is 1 sim I'm pretty bummed and pissed off, especially since my order tech sheet says dual sim.

I was just looking at the spec page on their website, and it says "Single nano-SIM slot". Fire up my VPN and go to the UK page, dual sim. Also, black version not available on US store.

nightpanda2810 said:
I was just looking at the spec page on their website, and it says "Single nano-SIM slot". Fire up my VPN and go to the UK page, dual sim. Also, black version not available on US store.
Click to expand...
Click to collapse
That's a brilliant idea. Will you post if it works?

ctonylee1965 said:
That's a brilliant idea. Will you post if it works?
Click to expand...
Click to collapse
I'm currently on the fence, mostly cause my current phone works and performs fine. But if I do, I'll post here.

I can report, I just got my US variant (AA) and the dual sim tray slot on the backside like normal had a plastic bar preventing the use of dual SIM...I wonder if it's also disabled in software as well if one were to get a dual sim card tray...

I just tried my dual SIM tray from my OnePlus 8 Pro and it will only recognize a SIM in the front slot. I assume the functionality is disabled in the rom.
BTW, the 8 Pro SIM tray doesn't quite go in all the way, it has a thicker red gasket for sealing than the 9 Pro does. It still works, just not flush with the body of the phone.

bjevers said:
I just tried my dual SIM tray from my OnePlus 8 Pro and it will only recognize a SIM in the front slot. I assume the functionality is disabled in the rom.
BTW, the 8 Pro SIM tray doesn't quite go in all the way, it has a thicker red gasket for sealing than the 9 Pro does. It still works, just not flush with the body of the phone.
Click to expand...
Click to collapse
I tried this as well, same result. It is hard to remove the 8 Pro SIM tray from the 9 Pro if you push it in.
Is the international ROM available to flash? I want to see if flashing that will make it recognize the second SIM with the 8 Pro's SIM tray.

I am very interested in this as well. I pre-ordered this phone because it said it was Dual-SIM for the USA. The following day, they edited it back to single-SIM.
If this can be worked around via getting a dual-SIM tray and flashing the global ROM, maybe I won't have to return it after all.

I can't believe we even have to have this discussion with a $1000 phone from a brand that has always had dual sim functionality. Argggggg...... It's going to make my head explode!

ctonylee1965 said:
I can't believe we even have to have this discussion with a $1000 phone from a brand that has always had dual sim functionality. Argggggg...... It's going to make my head explode!
Click to expand...
Click to collapse
Right? The whole reason I splashed out for a carrier-free "premium" phone was to not be held down by any idiotic restrictions- but lo and behold OnePlus bent over backwards for T-Mobile. The worst part is that it's literally the same hardware, we just got a single-slot SIM tray and software to lock us out of the second slot.
It boils my blood that you can see the second set of SIM contacts in there and can't use them without jumping through hoops.
Mine's sitting in the damn box still, because I'm not using it until I know I can utilize both SIMs I have on it.

carbondog said:
Right? The whole reason I splashed out for a carrier-free "premium" phone was to not be held down by any idiotic restrictions- but lo and behold OnePlus bent over backwards for T-Mobile Verizon. The worst part is that it's literally the same hardware, we just got a single-slot SIM tray and software to lock us out of the second slot.
Click to expand...
Click to collapse
I suspect it's Verizon's fault to forcing it as Single SIM on the software side. Verizon gimped previous Android models in a similar way previously. Pixel 3 eSIM was disabled on Verizon-sold models, and they forced OnePlus to make separate variants of the OnePlus 8 for both Verizon and Visible.
They knew OnePlus would want it certified for 5G mmWave, and that was probably Verizon's 'terms' for getting it cleared.

GenesisDH said:
I suspect it's Verizon's fault to forcing it as Single SIM on the software side. Verizon gimped previous Android models in a similar way previously. Pixel 3 eSIM was disabled on Verizon-sold models, and they forced OnePlus to make separate variants of the OnePlus 8 for both Verizon and Visible.
They knew OnePlus would want it certified for 5G mmWave, and that was probably Verizon's 'terms' for getting it cleared.
Click to expand...
Click to collapse
This is actually a very good point that I hadn't considered. I hate how anti-choice the US wireless market is.

carbondog said:
I am very interested in this as well. I pre-ordered this phone because it said it was Dual-SIM for the USA. The following day, they edited it back to single-SIM.
If this can be worked around via getting a dual-SIM tray and flashing the global ROM, maybe I won't have to return it after all.
Click to expand...
Click to collapse
the second sim does not even fit in the the sim slot, it kinda looks like a microSD can but I don't have one to try.
Yeah I was kinda upset about this too, b/c I used my OP7Pro for personal and work phone with 2 sims.

Bradl79 said:
the second sim does not even fit in the the sim slot, it kinda looks like a microSD can but I don't have one to try.
Yeah I was kinda upset about this too, b/c I used my OP7Pro for personal and work phone with 2 sims.
Click to expand...
Click to collapse
The tray has been deliberately rendered useless on the second side. I tried it with the tray from the 8 Pro which fits two SIMs properly, but the software won't recognize the second SIM.

carbondog said:
Right? The whole reason I splashed out for a carrier-free "premium" phone was to not be held down by any idiotic restrictions- but lo and behold OnePlus bent over backwards for T-Mobile. The worst part is that it's literally the same hardware, we just got a single-slot SIM tray and software to lock us out of the second slot.
It boils my blood that you can see the second set of SIM contacts in there and can't use them without jumping through hoops.
Mine's sitting in the damn box still, because I'm not using it until I know I can utilize both SIMs I have on it.
Click to expand...
Click to collapse
So frustrating. US telcos need more consumer-friendly regulation so they can't engage in anti-competitive behavior like this.
I put mine back in the box. Offering it to my wife to use, and if she doesn't, this is going back for a refund. Ordered the exact same phone from Amazon Italy, that should have dual SIM. ETA Apr 1-2.

pavankp said:
So frustrating. US telcos need more consumer-friendly regulation so they can't engage in anti-competitive behavior like this.
I put mine back in the box. Offering it to my wife to use, and if she doesn't, this is going back for a refund. Ordered the exact same phone from Amazon Italy, that should have dual SIM. ETA Apr 1-2.
Click to expand...
Click to collapse
That's not a bad idea, I think I'll do the same since I know my wife doesn't need dual-SIM. She probably won't want it though, haha. Let us know how that works out, if it's smooth sailing then I might just do that as well. I wish I knew this before ordering from OP directly, I'd have just gone to Amazon first.

carbondog said:
That's not a bad idea, I think I'll do the same since I know my wife doesn't need dual-SIM. She probably won't want it though, haha. Let us know how that works out, if it's smooth sailing then I might just do that as well. I wish I knew this before ordering from OP directly, I'd have just gone to Amazon first.
Click to expand...
Click to collapse
Just a heads up bro.
If you live in North America like me ordering the OnePlus 9 series from Amazon Italy makes no sense as their variant is UK version which misses many LTE & 5G bands that we need in USA & Canada! I almost put the order through before noticed that is a UK variant.

samteeee said:
Just a heads up bro.
If you live in North America like me ordering the OnePlus 9 series from Amazon Italy makes no sense as their variant is UK version which misses many LTE & 5G bands that we need in USA & Canada! I almost put the order through before noticed that is a UK variant.
Click to expand...
Click to collapse
The bands are almost always different. I think they do it on purpose so people in North America are stunted if they do a gray market purchase.
Why does the North American models have 5G band 78 for the EU but they don't have 71 or n260, etc.. They do it on purpose to screw us over.

samteeee said:
Just a heads up bro.
If you live in North America like me ordering the OnePlus 9 series from Amazon Italy makes no sense as their variant is UK version which misses many LTE & 5G bands that we need in USA & Canada! I almost put the order through before noticed that is a UK variant.
Click to expand...
Click to collapse
Damn, man- this got me thinking, so I threw together a quick comparison graphic of the bands, which are missing in their respective models. Top is from the US OP page, bottom is from Spain's.
I was planning on using mine with Verizon, looks like that might not be a good idea.
Looks like the NA version should work in EU with minimal problem, but the EU version is missing many NA bands. 100% due to carrier pressure, disgusting.
If anyone can manage to successfully enable the second SIM slot of a NA variant, that looks like the way to go.

I search around and found that iphone US version are also single sim and they are able to make it to dual sim only if they open the phone and replace the actualy sim inserted piece on the motherboard. I watched the tear apart video of oneplus 9 pro which the sim card piece on the motherboard is also detachable without remove the whole motherboard. I think the would work. Simply use a dual sim tray would not work.

Question Will we ever see dual-SIM enabled on the NA model?

We can finally order dual-SIM trays via eBay as of today. What are the odds of being able to enable that second slot?

It might need some time. I read from other post that oneplus 8 pro took a year before a low that feature. now oneplus 9 pro only have one sim tray so it might talk even a longer time for them to release that feature. I am more depending on the people who know how to customize the rom and add feature . So just stay tune at different forums.

OP9Pro normally comes with a dual SIM. Just flip over your sim tray and insert the second sim. Voila!

carbondog said:
We can finally order dual-SIM trays via eBay as of today. What are the odds of being able to enable that second slot?
Click to expand...
Click to collapse
That's great news. I returned by OP9P NA variant, but don't have a global variant yet. Shouldn't it just work with the NA variant if we flash a global ROM on the same device? It looks like it has pins on both sides.

pavankp said:
That's great news. I returned by OP9P NA variant, but don't have a global variant yet. Shouldn't it just work with the NA variant if we flash a global ROM on the same device? It looks like it has pins on both sides.
Click to expand...
Click to collapse
Not that simple I think. I already flash to EU tom but it does not second sim in the settings. I think it might need wire flash of all components including baseband

amandeepparmar said:
OP9Pro normally comes with a dual SIM. Just flip over your sim tray and insert the second sim. Voila!
Click to expand...
Click to collapse
it doesn't for USA model.

fifasax said:
Not that simple I think. I already flash to EU tom but it does not second sim in the settings. I think it might need wire flash of all components including baseband
Click to expand...
Click to collapse
Oh no. Does OnePlus publish those components, or are we out of luck until someone figures out a way to get them? The EU variant I have on order doesn't support one AT&T LTE band, so would much rather use an NA variant with dual SIM enabled.
If the EU variant shows up at my door before someone figures out how to make dual SIM work on the NA variant, then I will just use it even with the missing LTE band.

pavankp said:
Oh no. Does OnePlus publish those components, or are we out of luck until someone figures out a way to get them? The EU variant I have on order doesn't support one AT&T LTE band, so would much rather use an NA variant with dual SIM enabled.
If the EU variant shows up at my door before someone figures out how to make dual SIM work on the NA variant, then I will just use it even with the missing LTE band.
Click to expand...
Click to collapse
I saw one guy on Reddit complaining of the same situation we're in- ordered the phone when it said dual-SIM and trying to return it afterward.
He claims OP customer service said dual-SIM would be enabled via update in the future. While I hope that's true, it's the first and only time I saw that said anywhere. Could've just been said to try and avoid return. Even if it does happen, it'd probably be a ways off.

carbondog said:
I saw one guy on Reddit complaining of the same situation we're in- ordered the phone when it said dual-SIM and trying to return it afterward.
He claims OP customer service said dual-SIM would be enabled via update in the future. While I hope that's true, it's the first and only time I saw that said anywhere. Could've just been said to try and avoid return. Even if it does happen, it'd probably be a ways off.
Click to expand...
Click to collapse
I chatted with OnePlus customer service two different times. Both agents tried to talk me out of wanting Dual SIM, but were very clear that it is single slot only for the US. One even cited spouted some bull**** about doing that to optimize 5G performance on US networks.

pavankp said:
Oh no. Does OnePlus publish those components, or are we out of luck until someone figures out a way to get them? The EU variant I have on order doesn't support one AT&T LTE band, so would much rather use an NA variant with dual SIM enabled.
If the EU variant shows up at my door before someone figures out how to make dual SIM work on the NA variant, then I will just use it even with the missing LTE band.
Click to expand...
Click to collapse
I guess we have to wait to see if anyone can figure out how. At least, just upgrade to a newer version of EU tom does not work. Not sure if you for flash everything and reset from adb is the same

i have a bnib stellar black chinese version dual sim 8/256 oneplus 9 pro for sale. I am in SF bay area.

Will it work if i have a Dual Sim Oneplus 9 from Malaysia, install NA rom to open more BANDS ? The malaysia OnePlus 9 has the same 5G bands as in UK, but lack of some US 5G bands like n71. All CN variant do not have B13 band, therefore, not supporting Verizon LTE nicely. All ebay sellers who claimed dual sim with 12GB RAM and 256GB storage are mostly CN variant. I'm better off with EU/UK or MY. Hong Kong spec is the same as USA with dual sim. If anyone wants a dual sim and want mostly all US bands supported, Hong Kong Oneplus seems to be the right fit. Only if we can get it from HK
MY Spec
OnePlus 9 Specs
oneplus.com
HK Spec
OnePlus 9 Specs
www.oneplus.com

amandeepparmar said:
OP9Pro normally comes with a dual SIM. Just flip over your sim tray and insert the second sim. Voila!
Click to expand...
Click to collapse
Funny, I don't have the option.

amandeepparmar said:
OP9Pro normally comes with a dual SIM. Just flip over your sim tray and insert the second sim. Voila!
Click to expand...
Click to collapse
wait what?! both SIM fits in the same compartment ?
wouldn't that be too tight?
mine only has a slot for 1 SIM

The dual sim versions have 1 sim on each side of the tray.

Mine came with dual sim out of the box and is working perfectly.
I really like how I don't have carry around 2 phones anymore.

flaxjef said:
Mine came with dual sim out of the box and is working perfectly.
I really like how I don't have carry around 2 phones anymore.
Click to expand...
Click to collapse
Do you have the US version?

I was very disappointed that the US version didn't come with a dual sim. I ordered mine at launch, when their website said that it had it.. Anyway, I finally figured out an acceptable replacement option for mine. I did have 1 sim for my personal number and a second sim for my work number (worked great on my OP 6T for a couple of years now). After playing around with things, I finally ended up porting my work number over to Google Voice (1 x $20 fee) and installed the Google Voice app on my phone. Now I essentially have 2 #'s on one phone, just like having a second SIM, but no cost to my carrier. I can receive calls and txt's for the # I ported to GV. Wasn't quite the solution I was hoping for, but now I no longer pay for that line.

lastscout said:
Do you have the US version?
Click to expand...
Click to collapse
I don't think is a US variant. As far as US Variant is concern, is single SIM. Anyone that is using Dual sim could be CN or EU/UK Variant. If it is indeed a US variant, then I'm interested to know where the source to get it then . Those variants have fewer 5G sub-bands compared to the US except HK. I just hope that Oneplus has the hardware embedded and is just a matter of software activation. Samsung Note20 new firmware patch also opens up their eSIM support.

Ops400 said:
I was very disappointed that the US version didn't come with a dual sim. I ordered mine at launch, when their website said that it had it.. Anyway, I finally figured out an acceptable replacement option for mine. I did have 1 sim for my personal number and a second sim for my work number (worked great on my OP 6T for a couple of years now). After playing around with things, I finally ended up porting my work number over to Google Voice (1 x $20 fee) and installed the Google Voice app on my phone. Now I essentially have 2 #'s on one phone, just like having a second SIM, but no cost to my carrier. I can receive calls and txt's for the # I ported to GV. Wasn't quite the solution I was hoping for, but now I no longer pay for that line.
Click to expand...
Click to collapse
You do know they make an app called second line right? So you don't need to pay for 2 plans

Question Can I "convert"physical SIM as eSIM on Pixel 6 pro?

Just got the phone. Makes nice photos, so I'd like to make it my primary phone over Xiaomi 11 Pro I had until now. Also, it's a Pixel, so I'm hoping to finally go back to custom ROMs and kernels after a (too) long time of chinese lock-out from such atrocities (as rooting, unlocking and custom ROMs are)
However, I realised that the phone actually only has one SIM slot, not two as advertised in the shop (without looking carefully at the fine print)
Anyway, I have two SIM cards, none from an operator that would be eSIM compatible.
Is it possible to "convert" a physical SIM to an eSIM somehow?

as long as your provider supports esim you can swap

velis74 said:
Just got the phone. Makes nice photos, so I'd like to make it my primary phone over Xiaomi 11 Pro I had until now. Also, it's a Pixel, so I'm hoping to finally go back to custom ROMs and kernels after a (too) long time of chinese lock-out from such atrocities (as rooting, unlocking and custom ROMs are)
However, I realised that the phone actually only has one SIM slot, not two as advertised in the shop (without looking carefully at the fine print)
Anyway, I have two SIM cards, none from an operator that would be eSIM compatible.
Is it possible to "convert" a physical SIM to an eSIM somehow?
Click to expand...
Click to collapse
I am currently using At&t with an esim, and I have Verizon on a physical sim. It works beautifully.

Perhaps I was unclear: I do not have an option of QR code or download of an eSIM. I only have two old-style physical SIM cards. I need one of those converted to eSIM.
Is this possible using some custom tool, some custom ROM maybe supports that or anything like that?

No you cannot. You have to call your cell service provider and ask for an eSIM activation because eSIM uses your IMEI2 instead of IMEI1.

You can't convert a sim to an esim. You have to get an esim from your provider (if they support them) and then they will port your number to the new esim once it is loaded onto your phone. Some can do this pretty much instantly, many like porting on physical sims it can take a few hours, or even a day or so to port across.

Also keep in mind, that many carriers send out the e-sim in physical format (they give you a piece of paper with a QR code to scan), so you will have to wait for a couple days until you can use E-SIM (some carriers allow you to access the QR code in their respective app/website, so keep that in mind and chose accordingly).

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.
Click to expand...
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!
Click to expand...
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
Click to expand...
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
Click to expand...
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.