A free app for Android, by Droidhut.
DiceBag is the perfect tool for both players and GMs.
Players can quickly and conveniently pre-program the damage, hit points, and bonuses for each die.
Each roll can be customized by the user to include any bonuses, damage, or hit points. The dice roll will also display the number of hits, damage, and bonuses for each die.
GMs can also customize the results of their dice rolls. DiceBag includes four preset outcomes, or you can choose to have it generate a random result.
The user can also choose to display the names of the monsters, spells, or abilities that will be rolled.