Develop Bugs

[Q] How Does the Android OS Work?

Disclaimer: I am only a flasher. I do, however, contribute to the forums, donate to devs and also use the paid version of good apps.
My question is: How does Android work on our phones?
You have hardware (HTC Incredible); you have a carrier (Verizon, in my case); you have an OS (Android, obviously); you have a radio; you have a ROM; you have a kernel; you have themes, you have skins and you have apps. How do all these pieces interact? Just curious.

This is a really good question that should be answered in laymen's terms. I'm surprised it hasn't been answered yet.

I also thought it would have been answered by now. However, I think the developers (who would be the best folks to answer this question) are busy working with the Gingerbread source code to build new ROMs for us.
This is what I have figured out so far but I'm not sure if my analysis is correct:
After selecting your hardware and carrier, the OS is the most important element. Most of us are currently on Froyo (2.2). I have seen some screen shots showing the OS version to be "2.2.1" but I am not sure why. Google (I think) has released the source code for Gingerbread (2.3) and the developers ("devs") are hard at work producing new ROMs as I post this.
I gather that it is best to stay away from trying out different radios ("basebands"). Most of us are using 2.15.00.07.28.
I think the ROM takes the OS and re-works the user interface by adding, removing and changing the various screens and "features" of the OS. For example: the ROM can be written to take out the stock music player and substitute a music player that the ROM developer prefers. I think this is called "baking in an app". I believe the ROM developer can also create an overall "look and feel" that can be quite different from the stock OS. For instance, the ROM can be "colored" in black and red (rather than the stock green) and the stock font can be changed to something the developer prefers. In other words, the ROM is what you see and use on a daily basis.
Now this is where things get a little fuzzy: the kernel. I think this is kind of a behind the scenes element that governs the performance of a ROM. It greatly affects things like battery life, time to charge the battery and the "speed" of the phone. The kernel is where the phone can be "over-clocked" and "under-volted" should you want to do those things. I gather that once you select a ROM, you can try different kernels without changing what the various screens look like on the phone. I believe this is the way most people do it (pick a ROM and try different kernels with it). I don't think the other way really works (pick a kernel and try different ROMs with the kernel).
Next comes themes and skins which really only affect what you see on the various screens without do anything about battery life or the speed of the phone. I haven't played with these much.
Finally, I forgot to put WALLPAPER on the list in the original post. I believe this only appears as a background image on the home screens.
If any reader sees errors in my layman's analysis, please, by all means jump in and correct me. Per my disclaimer in Post #1, I am just an ordinary user and this analysis could be flawed or incorrect in whole or in part.

Everytime I try to answer a question like this, I get too complex about it and leave more questions than answers. Then someone comes along and says "It's like Windows or Linux or MacOS on a PC", and that's that. Well they're right. Those OS's tell the PC's that they are PC's and essentially all OS's do the same things.
Here's my simplified new list:
1) Hardware on phone :: meaningless without OS
-- (android OS - or any other OS)
2) Linux kernel understands hardware like touchscreen, radios, I/O (drivers/modules). Of course it also understands how to schedule processes and all those "kernel tasks".
3) Libraries provide APIs (Application programming interface) to userspace code (like APPS).
4) Userspace (apps, scripts, libraries) provide user control over the phone.
--
Together they work in harmony (we hope) to make the phone realize it is a phone and allow us to use it as such. (well, a smartphone, so many things other than a phone).
Here's a simple example: You touch the phone icon which is in userspace, and it brings up the userspace phone app. As soon (or before) as you touch some buttons, dial a number, it is using the API to the driver in the kernel that actually understands the phone hardware/radio. Also userspace controls GUI which is also requiring API to some form of OPENGL API that is requiring device drivers that get the touchscreen/LCD display. and so on.
--- Hashi
PS: I realize there are a thousand things wrong with this representation, but hey, it's a start. Feel free to fix it up if you're inclined.

Attempting development for Gingerbread. (Long post/discussion)

Hello everyone...I'm planning on trying to develop a gingerbread kernel for AOSP because we don't really have support anymore and everyone has moved onto developing for ICS (not that this is a bad thing). I figure in my spare time I might as well try to learn and develop for our phone. Let me start by saying I was never really into phones/smartphones/rooting, or software development, but I've always been fascinated by Linux in general. I've played around using a number of Linux distros, but I've never really done anything intensive with them (modified their kernels, etc.) but I am vaguely familiar with terminal usage.
Anyways that was just my introduction. I've been running an ICS kernel on my AOSP GB system (specs/stuff in my signature) and while most advised against it, I find it to run pretty well. I'm not sure why it seems to run so well on my phone, but it's basically solved most of my problems (or at least it appears to have done that), but I know the kernel isn't "optimized" for my phone. Some major things people have said are that the ramdisking operations/system is totally different when comparing ICS and GB. This kernel that I'm using is running pretty well, even knowing this fact. What I was wondering is if I could basically get the ICS kernel, then "merge it" with a GB kernel's parameters that pertain to the ramdisk/other major options of GB. That would probably make it better. Also, people stated that multitouch issues for the DINC2 occured on Aeroevan's 0.8 kernel, but not on the 0.7 kernel. This was the changelog stated by aeroevan:
v0.8: Upstream CyanogenMod changes + small touchscreen driver update from HTC. Only tested on my CM7.2 Kang build.
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Click to collapse
So maybe this "small touchscreen driver update" is the thing that caused it, but I'm assuming many other kernels applied this update too? Maybe there is a way to roll back to whatever was in 0.7 in this sense to get rid of the multitouch bug that plagues some people.
I have a pretty powerful laptop, so development shouldn't be too bad. I plan on running Ubuntu 11.10 (or whatever people find suitable these days) in a Virtual Machine and I plan on compiling stuff from there. I am not claiming I know everything or that these things are correct....I am simply just throwing out some brainstorming to get some ideas out there. I know GB is "old", but I (and some others as well) enjoy it's stability and that it generally functions perfectly. Maybe this thread will get a look from popular devs, or maybe it'll get a look from people who just know this stuff. Thanks for reading, and sorry for the length of the post.

Looking forward to your progress on this.
Sent from my ADR6350 using xda premium

It would be nice to have another kernal for AOSP other than aero.

Your help in developing AOSP kernels would be fantastic.
Thanks given. Because I am hard of hearing I cannot use any of the kernels (even Evan's) and have to stick to Sense

[Q]Best Kernel To Use With Stock 4.3?

So this is the first time I'm really customizing my phone besides when I rooted it months ago. Now, I've just installed the new touchwiz 4.3 ROM courtesy of this helpful package and I'm looking into installing a custom kernel to get the most out of my phone. Right now its just running the default kernel that was included in that package: "3.0.31 g1ac4b4a-dirty [email protected] #1"
So, I'm wondering if anybody with a bit more knowledge and experience could lend me some advice on what kernel I should seek out. I don't really need any customization, like overclocking and undervolting (because I have no idea how to fiddle with that stuff without breaking something), I just want something that is optimized to be quick and battery efficient.

CaptainStormagon said:
So this is the first time I'm really customizing my phone besides when I rooted it months ago. Now, I've just installed the new touchwiz 4.3 ROM courtesy of this helpful package and I'm looking into installing a custom kernel to get the most out of my phone. Right now its just running the default kernel that was included in that package: "3.0.31 g1ac4b4a-dirty [email protected] #1"
So, I'm wondering if anybody with a bit more knowledge and experience could lend me some advice on what kernel I should seek out. I don't really need any customization, like overclocking and undervolting (because I have no idea how to fiddle with that stuff without breaking something), I just want something that is optimized to be quick and battery efficient.
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Click to collapse
This thread will probably get locked, because their is no BEST kernel. Not all gs3s are created equal. I've learned that battery efficiency is based on a lot of different things, such as, bloatware removal, apps that run continuously, how many radios you have turned on, even how long your backlight stays on. You should allow any kernel to set in for a couple of days before judging battery life.
sent from my GS3

as of right now there is only one kernel any way. lol

P600 stuck on 4.4.2 - need upgrade for speed and reliability

I have an Australian version (XSA) of the Note 10.1 sm-p600 which was only ever upgraded to 4.4.2 (latest official release).
I find the performance sluggish when playing games (eg Clash Royale) and want to see if a new ROM will improve the speed but want minimal fuss. I would like to know people's suggestions of which ROM to use that will give me a faster but still stable experience.
Is the official 5.1.1 any good? Do I need to go custom? I want to avoid having to do complicated installs as well if possible.
I mostly play games and watch YouTube on it and maybe some sports apps to get scores. Nothing that really requires root (and some of the sports apps don't like root).
Thanks in advance.

Just checked my build and it looks like it is already on 5.1.1 - I must have updated it last year and forgotten.
Still not happy with the load times of Clash Royale, any other suggestions about making the tablet run faster? It seems to still have a decent processor and RAM despite being a few years old.

Well, you're running 5.1.1 right? Probably the only thing left is to go to Development section and install Prime Kernel V6, it's the last version for lollipop touchwiz. That one has a couple of tweaks to improve the standard performance offered by stock/factory software. Make sure to backup everything, and then flash the zip. Updating kernel has no need to wipe or reformat anything so no data is lost, but do it just in case.
To get more juice out, you'd have to install custom ROMs, like LiquidDeath from the Original Development section, that has a couple of new stuff like the updated GPU driver ported from marshmallow touchwiz apparently, and from my subjective view, performance is better along with increased battery life.
I don't do much gaming, but on stock 5.1.1 with stock kernel I usually get around 7 hours screen on time browsing the web, but with LD I can go around 10 to 11 hours easy with the same usage.

Thanks. I'll check out the kernel first.
Would you suggest LiquidDeath or LineageOS?

Sorry for the late reply, lol. I assume you've been running touchwizz/stock Samsung lollipop this while, but using that custom kernel I've mentioned? How was the experience? If that works fine with you, I believe there's no need for custom ROMs.
I test and run random ROMs many times, liking to flash stuff and all. If you want to try out the waters, the most rock-solid, no-issues release so far is probably the last release of LiquidDeath, mostly because it has less crud, and therefore fewer potential to go wrong. Lineage is good too, but I prefer keeping it simple.

Note II AT&T Rom choice - Advice

Hello all,
I may get teased a little bit for this one - but I am a bit of a traditionalist. Even as an IT guy, I tend to shy away from custom, enhanced or otherwise modified ISOs of windows. Not because I am afraid of them... I just like the "stock" look. I would like to stick to the same thing on my phone.
I am still running the stock version of my ATT firmware, 4.x.x. I like it just fine, and it suits my needs for the most part - (Other than the ATT bloatware that crashes constantly for several minutes upon reboot)
However, my device is beginning to slow down and I find myself using Chrome more and more because the older stock browser does not seem to want to render some sites very well. I expect it is only a matter of time before I start running into "sorry, you cannot run this app" type of issues.
So on to my questions....
1. Will upgrading to 6.x or 7.x improve the performance on my device?
2. If so, I see there are a ton of apps to choose from. Is there one specifically that is "less modified" or at least enables some sort of "gotta-have-it" functionality?
3. Can you elaborate on why you chose to move from the stock rom? I understand there are alot of "testers" on this forum who like to play with things. However, my phone is used heavily for work purposes. Simplicity and Stability remain key drivers for me.

Changing to a custom ROM may improve some areas of performance while decreasing in others such as battery life, camera, and stability.
By apps, I assume you mean roms. I can't make any recommendations as I have not had a note 2 for a few years but I have found that custom ROMs based off a stock rom are pretty stable. I always like to start with a very bare-bones ROM and add functionality via apps as needed.
I have moved to custom ROMs in the past when apps won't run on the phone's stock rom.

I've run my note 2 on DN3 for a number of years. You can still find a link to the thread in this forum and you will need to root your n2.
Not hard. 1 advantage is you can remove the bloat and it's still a rom that runs well on our device since it was built for our device in it's prime.
If you have any questions send a PM. Happy to help.
wisem2540 said:
Hello all,
I may get teased a little bit for this one - but I am a bit of a traditionalist. Even as an IT guy, I tend to shy away from custom, enhanced or otherwise modified ISOs of windows. Not because I am afraid of them... I just like the "stock" look. I would like to stick to the same thing on my phone.
I am still running the stock version of my ATT firmware, 4.x.x. I like it just fine, and it suits my needs for the most part - (Other than the ATT bloatware that crashes constantly for several minutes upon reboot)
However, my device is beginning to slow down and I find myself using Chrome more and more because the older stock browser does not seem to want to render some sites very well. I expect it is only a matter of time before I start running into "sorry, you cannot run this app" type of issues.
So on to my questions....
1. Will upgrading to 6.x or 7.x improve the performance on my device?
2. If so, I see there are a ton of apps to choose from. Is there one specifically that is "less modified" or at least enables some sort of "gotta-have-it" functionality?
3. Can you elaborate on why you chose to move from the stock rom? I understand there are alot of "testers" on this forum who like to play with things. However, my phone is used heavily for work purposes. Simplicity and Stability remain key drivers for me.
Click to expand...
Click to collapse