Once you have put it on and let it set you can't really change it again without destroying it, but when you put it on you have all the time you want as long as the protector is still wet.

BestSkinsEver also make these kind of protectors at a far cheaper price than Zagg.
Got one for my brother's birthday today - he just got a brand new EVO so i m sure he ll be happy about it andddd i saved myself some money with the 20% so all good