One of the best-selling apps of the year in the news category, according to Apple, is Circa. The app was also chosen by Google as one of the best Android apps of the year.

Circa calls itself "the first news organization to write strictly for the mobile lifestyle,"and is an unusual app that tries to simplify the process of absorbing news information on the go.

The app breaks down the news into brief stories, something like extra-long tweets that can be updated or expanded as news events unfold. It uses clever push notifications on iOS to draw a reader's attention to the news, and it uses other cues like vibrations to alert a smartphone owner to breaking news.