PlayerPrefsExtended.Save() - Save all keys. PlayerPrefsExtended.DeleteAll() - Delete all keys from PlayerPrefs. PlayerPrefsExtended.DeleteKey(string key) - Delete the specified key if it exists.

So, by and large, we should to save small data (such as level names, player location data, etc.) in PlayerPrefs, and all large data sets (for example, a screenshot of a level, data about player's ...