Didnt work at all! I just recently had to do a "system reset" due to my Gmail account screwing up....anyway, point being afterwards I had tons of duplicate contacts just like when I first purchased my iPhone. I was so excited when I found this app for free (usually $2.99), installed it, ran the analysis, said I had 50 duplicates, asked me about the ones I wanted to merge, went through those, and TA-DA >>> NOTHING! It said I was duplicate free! REALLY? I knew immediately when I read I only had 50 duplicates that it wasnt working correctly. Not only DO I HAVE (yes still have) a whole lot more than that, but to my surprise, it didnt even get rid of the 50 that it stated I had! Oh Well - on the bright side of things at least I didnt have to pay $2.99 so only my time was wasted and not my money!