Twitter announced two changes to its iPhone app Wednesday afternoon, introducing photo tagging and the ability to post up to four photos in one tweet. Both represent the ways in which Twitter is slowly but surely moving beyond the boundaries of its traditional 140 character limit. Here’s what the new photo collage looks like in practice, from Time’s Alex Fitzpatrick. Both the photo collage and tagging features are the next step in the service’s effort of “moving the scaffolding of Twitter into the background,” as Twitter’s head of news Vivian Schiller said last week.