Gym owner here. For two days, this app stalls at login or says "check your internet connection" — on a connection that runs everything else fine, including Zen Planner's own website. I've reinstalled it, cleared cache and data — all 1.41 MB of it. The app stores nothing; everything lives on their servers. It's a window that can't look through itself. It's the app's own connection failing while standing next to a working internet connection — which, yes, is as dumb as it looks.