Android/Services
The Android Background Services module is a collection of related functionality that supports Mozilla's work on Android. Its remit is services, adapters, uploaders, downloaders, and the like that are not primarily user-facing, although UI is not excluded.
As of this writing (March 2013), this growing set includes Firefox Sync, product announcements the native updater, Firefox Health Report's native document manager, homepage snippets, and others.
Much of the code for Android services lives in the android-sync repo. Repository names are hard to change; pretend it's "android-services". Work in this repository is tracked by bugs in Bugzilla, but performed in Git branches and landed incrementally in mozilla-central.
Other work (e.g., the updater) lives in mozilla-central, typically as part of the mobile/ tree.