Flock, a new iPhone app from the people behind Bump, solves the first world problem of having to send photos to your friends through e-mail by creating shared photo albums with your friends with pictures that have similar metadata. It works like magic.
You know the situation, you're out with a bunch of friends and everyone's snapping photos with their iPhones and everyone wants each others pictures. What do you do? Ask them to email it to you? Hope they remember? Be surprised on Facebook later? With Flock, you don't have to do anything, and you'll still get the pictures.
The way Flock works is you take photos with any iPhone camera app and then Flock sees who you're Facebook friends with and finds anyone with the same camera metadata (location, time) and creates a shared album with your friends who were with you (you get an option to pick which pictures you share, of course). Your pictures, your friend's pictures, your other friend's picture from that night out are all popped into one album.
Flock even works with pictures you've taken before, in your camera roll. Basically, as long as your Facebook friends use Flock, you'll be able to easily share pictures with each other. [iTunes]