The At Bat app has consistently been one of the most popular sports apps on the Apple App Store as well as the Android Play Store. It is free and allows users to get live updates on scores and stats. The premium app costs $20, or $3 a month- "At Bat Premium offers Gameday, a graphical depiction of every pitch and every swing almost in real time. You see where runners are on base, how fast each pitch is thrown and where it crosses the plate". This app was created and is run by the MLBAM, who also run the leagues website.
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The already successful app grew even more popular when multi-tasking became available on an Apple product. AtBat made an update in February of 2016 allowing for viewing of multiple games at once-"along with picture-in-picture streaming for live video and highlights. What that means is that fans can now watch MLB.TV video outside the application". This feature is only available on select iPads, you have the choice to either use "Split View and Slide Over. The former lets you run two apps at the same time, side-by-side, on the same screen. The latter lets you open a second app without leaving your current app". This lead to users spending more time on the app which is important as far as chart rankings and advertisements are concerned. It definitely could be considered a quality which sets themselves apart from other sport streaming services.