There is a documentation error in the PlayerPrefs reference:
It says that playerprefs are stored in Android as [pkg-name].xml
This was true until a recent Unity version. When I upgraded to 5.3 I noticed that my game stopped reading a deeplink url I was writing from my launcher Android activity to SharedPreferences: [packagename].xml.
Now, it seems, I have to write it to [packagename].v2.playerprefs.xml for Unity to read it from PlayerPrefs.
So here’s how to access PlayerPrefs in android in Unity 5.3:
SharedPreferences playerPrefs = this.getSharedPreferences(this.getPackageName() + ".v2.playerprefs", Context.MODE_PRIVATE);
I don’t know if it’s ok to write question that includes the answer, but I thought other devs might run into the same problem.