[Android Q&A, Help & Troubleshooting] cybermaus:
How to DIY : Self root/gapps/playstore/locationfix/clean my ROM

This is a guide on how to root & cleanup your China ROM yourself. It will probably work on all ICS China phones. But it requires & starts with the availability of a recovery image for your phone

There are in fact a few steps:

- Get a proper recovery image for your phone.

- Root it by installing Chainfire's root package

- Install Google GMS ('GAPPS') to get Play Store and Localisation to work

And optionally

- Install Mobile UncleToolset

- Install an extra small fix with location services

- Install an extra small fix with latest APN list

- Install an extra fix to remove well known Chinese system apps

Recovery image

The Recovery Image allows you to boot into an alternative small Linux that you can then use to update the main Android. Updates usually come in "update.zip" scripted files. And the recovery has some other utilities like backup or wipe the entire phone. Getting a working recovery for your phone is step number one, because if you have a recovery, you can do everything else.

To check if you already have a recovery: Well, try to boot into it. The boot sequence may vary with the phone, but on MediaTek phones it is usually to replace the battery and then press&hold both volume buttons while powering up. I have seen it where you need to actually press the power button a split second before pressing both volume buttons. Try a few times, replacing the battery each time.

If you get to a screen that reads CWMR or CWMR Touch (short for ClockWorkModRecovery), you are all set and can continue with rooting. CWMR it is the most common open recovery image. If your recovery is closed, then you need to search the web for a working recovery for your specific model. Each brand and model needs its own recovery, because screen drivers, buttons and partition tables may differ.

Search the web is the best advise. Search wide and search deep. If you cannot find any recovery, then see if you can find a full ROM for your phone. If you have a working ROM image, then there are people on XDA that can make a recovery for you, but typically you need to show/prove that you have really tried to find one yourself.

Flashing a recovery

If you do find a recovery, that you suspect is the correct one for your ROM, then comes the scary part: Flashing the recovery to the phone.

This paragraph is specific to Mediatek based phones. On different hardware you also need a recovery, and once you have a recovery, you can use the other parts of this post, but how to flash other hardware, I do not know, sorry

Flashing using the flash tool is scary to new users. Because new users suspect that if they mess it up, the phone dies. And this is correct! But if you only flash the recovery.img part, you should be fairly safe. Read this manual on flashing. Getting the USB driver installed is sometimes a bit tricky, you may also want to read post #21 and post #25 for help.

I have seen several people asking 'where to find the scatter file'. Well, it comes with the ROM you want to flash. If your ROM file does not come with a scatter file, then is not a ROM file that can be flashed with the flash utility, but with an open recovery.

Rooting

Once you have a working recovery, the rest is simple. For rooting, simply install (from inside the recovery) chainfire's "CMW installable ZIP"

Link to his post: (ignore his big red 'requires root' warning). The file you need is labeled "CWM installable ZIP" at the bottom. Direct link to the file you need to install via recovery update.zip

This usually works by putting the zip file on the SD card (its name can be anything, though for some limited recoveries it sometimes must be named 'update.zip'), booting into recovery, and selecting the zip file to update.

Google GMS (Market/Play Store, Location, etc)

Simply install the latest Google Mobile Services (better known as GAPPS) from CyanogenMod V9. This is their explaining wiki from CyanogenMod

The file you need is called gapps-ics-20120429-signed.zip for ICS and gapps-jb-20121212-signed.zip for JB and can be found here. You probably also want to wipe your cache partition after doing this.

Mobile Uncle toolset

Just install this program apk (so not through the recovery, just install it normally). Or search the web for the latest one.

Fix location services

If location services does not work, do apply Google GMS (GAPPS) above. If it still does not work, it may be because the phone is programmed to use Chinese location services. This patch will tell it to use GMS. The patch will apply, and probably even work, on all ICS phones. But was originally made&tested on a Lenovo A750 ICS. Its called V1.3 because many people have downloaded the A750 v1.3 patch and used it on many MT6575 phones. It is still the same patch, except the update.zip is tweaked to work on any ICS phone, not only MT6575 ones.

Sometimes you also need to go into MobileUncle tool, the MTK Engineer mode, and in location settings. Depending on your exact model, somewhere in there is a NetLoc or NetLocation and a GeoCoding setting, with options of MEDIATEK and GOOGLE. Ensure they are set to GOOGLE.

After messing with location settings, it is best to also wipe cache.

Fix APN list (or My 3G does not connect!)

You can always add your own APN (Access Point Names) from the settings menu. Just add your own, and select that over the pre-build one. But this package will update with the latest list as maintained by CyanogenMod 9. The update.zip was made in such a way it should work on all ICS phones, Mediatek or other.

Clean well known Chinese system apps

<patch still coming>

==========================================

List of known recovery images for Mediatek Flash tool:

Lenovo A750 : 592zn : See also this post #607, nandroid backup does not work.

Lenovo A789 : 592zn or APKHOT

Lenovo P700i : My own, based on APKHOT with CWM.

Lenovo P700 : My own, based on CWMT / 592zn. nandroid backup will not work.

Lenovo A660 : My own, based on APKHOT with CWM

Lenovo S560 : My own, based on APKHOT with CWM (as yet untested)

Additional Recovery Images in this post.

If you feel you searched all over the web, and could not find a recovery for your model, and you next feel you should ask me or one of the other people on XDA to make you one (which I am not encouraging), than please be aware we need at least a 'standard ROM' for your phone to start from. Without it, I can do nothing. So go back out there, and find a standard ROM, does not matter what language, as long as it is for your specific phone model and known to work.

Also, as an extra warning : If you are flashing, and you experiment with 'suspicious' ROM sources, *never ever* flash the preloader, mbr, ebr uboot. Only flash those from a trusted source and if they belong to your exact brand and model phone.