Install time for Android application?

Question

Is there any way to determine programmatically the time at which an Android application was installed? I don\'t see anything in PackageInfo, etc.

--EDIT-- To clarify

Answer 1

When you install/update a non-protected app, it's apk file gets written to /data/app/package.name.apk, confusingly referenced as sourceDir (from my answer) resetting the timestamp to the current one. That's it.