i believe Joshua is a student, so hopefully he has just been busy of late and will rejoin us soon.
this is my most used app on my Z10, running for six to eight hours a day. i would say that i've put it through its paces but haven't had the freezing issues many of you have posted above. i have a 16GB microSD (~half filled currently) that has been in use for years, over many devices (always cleaned out and reformatted when going to its new home). i close the app when done and it gets a fresh start each morning (and sometimes once or twice more per day) to grab new 'casts, with a 40+ sub list. not running 10.1, but i would say this is heavy use without freezing. not trying to discredit, just trying to provide feedback to compare environment and behavior.
the only bad thing that has happened - just this morning actually - is i think it forgot the sub list, but i believe i caused this by closing it during a download refresh. so a back up or import/export option would be a nice addition to a future release version.