Saving Player Prefs external [External Storage] permanently

I recently leaned how to use Player prefs but a huge problem is that if the game gets deleted/Updated (on Android) the Player Prefs get lost and will be deleted as well.
Is there a possibility to avoid deleting Prefs or even Save Prefs to the HD or SDCard permanently? How do you save your games, save?
Thx for every Answer =)

actually this is a really good question. you can save all the player pref keys in xml format to a file OnApplicationQuit() using link textSystem.xml classes. so that you would have the back up always. whn you install the game again you have to read this file and set the playerprefs back. hope it is clear. if u want i can give you a rough code but not now since im not on unity rite now, ma be tmrrw.