"Glam out your selfies"
Instasquare does square your non-square photos for use in networks like Instagram, yes, but it also does so much more: it's a fully-fledged image editor packed with enough features to satisfy any amateur picture lover. Add filters, stickers, and text over your photo, then save it to your gallery or share it with the world.
The app is feature-rich without being overwhelming; everything included is useful for the amateur photo editor. There are tons of free sticker packs to download, which is great since you only use precious device space for the ones that you really want. It's an attractively designed app.
Professional photo editors will want to look for something more detail-oriented.