Yeah it has this web client that looks slick but
1) requires your phone to be turned on and online continuously, and
2) requires you to navigate two menus on the phone every time your phone reconnects to another wifi or anything.

Then I might as well just use my phone. Threema's web client is unusable for anything but one-off use. It gets slightly better if you buy into the Google backdoor stuff on your phone, then it allegedly reconnects automatically, but as I am not one of those people, it doesn't work for me.