Only thing I worry about it I take multiple photos of everything. So it isn't really deciding if I like the photo but deciding which one is best of that moment. Being able to compare multiple would be great.
I prefer Cleen (see http://www.producthunt.com/tech/...) because there's a third option -- it lets you swipe up to Favorite, moving photos into your iOS favorites folder. Something you might as well do if you're going to go through everything!
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