[Q] Android Porting. Why device specific?

[Serafym]

Hello all!!
I'm new to Android and i'm interested in learning a bit and maybe get involved with it but there are some things that i don't get about android and can't find the answers.
My main question is why Android which is based on Linux is so hard to get updates for all devices at once?
For example we got ICS lately why it's only available for Nexus S and not for all devices that support android?
In pcs if there is a new Ubuntu version every pc can get it no matter the hardware it uses as there are drivers for it.
Is it so hard to have drivers for all the android devices?
Why do we need to wait forever for the X company that makes the phone to build a new kernel?
Is it about the libaries?The drivers?
Say i got a device that is not supported by ICS what would i need to make it supported? I got my libs from 2.3.5 can i toss them to overlay compile and works? If not y not?
Thanks in advance for your answers and sorry if my questions are too noobish, everyone has to start from somewhere

 

[Theonew]

Hello all!!
I'm new to Android and i'm interested in learning a bit and maybe get involved with it but there are some things that i don't get about android and can't find the answers.
1. My main question is why Android which is based on Linux is so hard to get updates for all devices at once?
2. For example we got ICS lately why it's only available for Nexus S and not for all devices that support android?
- In pcs if there is a new Ubuntu version every pc can get it no matter the hardware it uses as there are drivers for it.
3. Is it so hard to have drivers for all the android devices?
4. Why do we need to wait forever for the X company that makes the phone to build a new kernel?
5. Is it about the libaries?The drivers?
6. Say i got a device that is not supported by ICS what would i need to make it supported? I got my libs from 2.3.5 can i toss them to overlay compile and works? If not y not?
Thanks in advance for your answers and sorry if my questions are too noobish, everyone has to start from somewhere

1. Manufacturers don't release updates for all their devices all at once (some not at all).

2. It's ready (most stable so far) for that device (SDK ports; (almost) official update)

- Not true. If you tried to place Ubuntu 12.04 LTS on a PC with a 368 MHz and 32mb ram, it would not run .

3. Yes. Android is on devices from many different manufacturers with many different designs and hardware.

4. See here: http://en.wikipedia.org/wiki/Linux_kernel (to know what it is). Different hardware will require different commands, etc. If the manufacturer doesn't release the kernel source, development cannot be done on that device (properly).

5. Yes and yes (much more too).

6. Create a working port from some other device (with similar hardware) which is supported. Sometimes. Some versions of android have backward compatibility of those files but ICS isn't really backward compatible which is why many ports of ICS (for various devices) don't have a working camera, etc. See the 2nd paragraph here: http://www.cyanogenmod.com/blog/cm9-progress-update.