[comex]

Apple's solution has the advantage of working with every app that reads from or writes to the camera roll - i.e. photos are downloaded on demand, and uploaded when taken - rather than only a single manager app. Of course, this is an unfair comparison, since third parties are not allowed to hook that deeply into iOS, but it is what it is.

[microtonal]

On the other hand, Carousel uploads are in Dropbox, automatically syncing to laptops and desktops, giving direct access to any application.