It's early 2015 now and the solutions listed above either don't exist any more, or aren't free if you have more than a few apps/testers.
The best TestFlightApp.com alternative that I have found is Crashlytics. They support iOS and Android (no Blackberry).
Here's some info on the service: http://www.crashlytics.com/blog/launching-beta-by-crashlytics/
And here you can sign up: http://try.crashlytics.com/beta/
My customers prefer it to TestFlight, and for me as a developer it's also easier because they have an OS X app through which I can upload the archives and invite new testers (TestFlight's desktop app was broken for me).
Another really nice feature that Crashlytics offers is that (if you enable this feature), the OS X app will automatically upload the symbol files. When the app crashes for your testers, you'll get an email (when it's a new issue) and you can view statistics and stack traces of the crashes that occurred.