An account’s posts can be shared publicly or with pre-approved followers. Users can browse other users’ content by tags and locations, and view trending content. Users can “like” photos, and follow other users to add their content to a feed.
The service was originally distinguished by only allowing content to be framed in a square (1:1) aspect ratio, but these restrictions were eased in 2015. The service also added messaging features, the ability to include multiple images or videos in a single post, as well as “Stories”—similar to its main competitor Snapchat—which allows users to post photos and videos to a sequential feed, with each post accessible by others for 24 hours each.