Instagram – iOS/Android – Free
If you love taking beautifully filtered pictures of your feet while on vacation, you’re no doubt familiar with Instagram. This ubiquitous photo sharing app has gone from cult status to the mainstream in just a few years.
Hardcore Instagram users complained last year when Facebook bought the company for $1 billion but the site just keeps growing. Last month Instagram added its 100 millionth member.
A never-ending stream of new filters has kept Instagram users snapping, and has made this the #1 photo-sharing app ever.