Despite working fine with the web version of the app, this Android version of Ticktick throws a validation error on my email address when I try to sign in because (according to Carol, a "dev" of the Ticktick team with whom I spoke about this on their help forum) my email address features hyphens. Tf?! Since when are hyphens in address so uncommon that they're not worth supporting. Terrible, imo, UX (both in app and for customer service).