Instagram is a mobile photo-sharing app, but it is also a social network. It's like Twitter with followers, only instead of real-time text updates, you provide photo updates. The app enables you to alter the photos you take with your phone by adding filtered layers that imitate the look of low-end film cameras.

These days, Instagram photos are cropping up all over Facebook and Twitter feeds. To casual viewers, these discolored, scratched-up, quasi-vintage photos with square, black film backdrops are of dubious quality--so why do users of the app find them so attractive?

It's important to consider this low-fi photo trend in context. Not everyone thinks the app has merit. In a Facebook poll of 2000 people, for example, respondents ranked the Instagram photos coming through their Facebook feeds among the , second only to baby photos.

Those who participated in the Facebook poll saw the Instagram app as too "gimmicky," producing "unnecessary photographic effects." Photography professionals such as also have their criticisms, saying that the app's users are lazy in applying its cookie-cutter filters to photos, which is unimaginative and bad artistic practice. For instance, different areas of a photo require different degrees of lighting or color adjustments--but Instagram applies the same adjustments to every photo.