SnapChat is a fast-growing photo messaging app that allows users to capture photos and videos and send along to their friends. Unlike other messaging apps, users can control how long their recipients can view their content by assigning a time limit of up to 10 seconds. Currently it is ranked #2 in free Photo-Video apps for iPhone, and #15 in free iPhone apps overall. As of November, 2012, there were 20 million photos being shared per day.
The app is a phenomenal hit with users between 13 to 25 years of age. It is often used to send funny self-portraits (aka "selfies"), group photos, and shots of users' surroundings and events they are participating in.