I have a new tablet that I installed CM12.1 and Pico GApps on. Here is a picture of the app screen:
I'd like to understand where each app comes from (either AOSP, CM or GApps). Is this something I can deduce from the apps' location on the filesystem, or the apps themselves perhaps ?
I have tried to find the information on the relevant sites for AOSP, CM and OpenGApps but have so far drawn a blank.
EDIT: Gathered additional content from the comments.
CM will list the package name of the apps in Apps Info. Those with com.cyanogenmod, org.cyanogenmod, cyanogen and com.cyngn (thanks @Izzy !) are certainly Cyanogen-specific, those with com.android are possibly AOSP-based and those with google are from Google. Alternately, list package names via adb shell pm list packages and find out the app name of a certain package (e.g. using adb shell 'dumpsys | grep -A18 "Package \[org.cyanogenmod.audiofx\]"').
For launcher entries that are parts of other apps, dragging them either to Apps Info or Uninstall will reveal what parent apps they belong to.
Explore your Pico GAPPS zip package to see what it installs. The apps might not be in APK format (OpenGAPPS compresses them in tar packages) but the filenames are still recognizable. Every app not in the package is part of CM itself.
As for which CM apps are based off of AOSP... I'd say it's hard to definitively find out without digging into CM sources.
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