How to localize Android OS for new locale I've been looking for the Android "localization project", assuming that there is one (like you have for LibreOffice or Mozilla) but so far, I have only found thousands of pages about localizing apps, but nothing about the operating system itself. Which suggests it's more complicated than I expected...


Assuming that it can be localized, anyone know if end users can then download and install such a new locale on their phones? I'm under no illusions about Scottish Gaelic ever getting shipped by default :/
If the answer is yes, then does anyone know how the localization process for Android actually works and where I need to go?


Thanks!
You'll need a copy of the OS with the needed locale. Since it's part of the OS it can't be added by a simple app download or anything. You can Spoof your locale string on any device but that app doesn't actually offer localizations beyond what shipped on your phone; it won't translate system text ect unless your phone has those localizations native.

As per the Android SDK docs:


  Note: The Android platform may support more locales than are included in the SDK system image. All of the supported locales are available in the Android Open Source Project.


You'll have to reflash your device with a system image that has your locale; the Android Open Source Project includes more locales but you/someone would have to actually compile them into a working system image/ROM. Making it work on your device is also another matter; ideally if your manufacturer has another official ROM out there with the locale on it you want, you should find that ROM and use it.

Unfortunately I don't know of any sites that have ROMs by supported locale.