What exactly happens when I install an android application?

Question

My guess is that the contents of .apk package are extracted somewhere, and the application is registered at some directory so that the application launcher or whatever can f

Answer 1

When you install an app, Android System copies its APK to "/data/app" folder and it named it by the package name followed by the installations number (how many times you install or update the app).

I tried to install an app manually by copying its APK and paste it in the /data/app folder and rebooted my device then it appears as an installed app and works perfectly.

Also I noticed in the link2SD app that any installed app has the folowing:

Apk located in /data/app/package-number.apk

Dex located in /data/dalvik-cache/data@app@package-number.apk@classes.dex

Lib located in /data/data/package/lib

Data located in /data/data/package

Cache located in /data/data/package/cache