Deploy iOS app to testers
When it comes to beta testing on iOS, there's really no other solid option. TestFlight is reliable, easy to use and has a set of great API's (albeit somewhat hidden).
We use Testflight for Alha & Beta testing of mostly corporate apps we create for our customers
American Bible Society - Digital Media
We previously used TestFlight to deploy test apps, but since Apple purchased them we've been using HockeyApp so that we can test both iOS as well as Android.