DiceMage

Fast, simple, easy
RPG Graybeard

Big icons showing real dice make it easy to select dice. No typing in formulas. Simply tap once for 1d or tap 3 times for 3d. It totals your taps. Even add other die types to the total. Using a flaming long sword? Tap the D8 and tap the d6 for the flames. Total shows up nice and large at the top with each individual role listed right below. Way faster than those complicated apps where you have to select a number and a modifier and a die type and then hit roll. The only drawback I find is that if you tap the plus one before you roll, it only adds the plus one once. I think that it should be if you put the plus one first, it adds plus one to each tap. But if you add the plus one after, it only adds it once. Also, the sounds are backwards. If you reset your roll, it sounds like dice rolling, but if you roll a die, it just "ticks". All in all, I highly recommend.