For the record, I did a lot more than "some trivial exploration". I started, stopped the app; rebooted the phone; connected the RC, disconnected, tried reconnecting, etc. Spent quite a bit of time on it, trying to figure out what's up.
So, in the event it might help other newbies to the Wonderphone with Go4, here's the "DUH" moment that I discovered (and never experienced on my iPhone):
When the app starts up cold, and you select "Equipment", the splash screen comes up with a Spark on it. That's a clue. I never noticed that and realized that if I'm trying to connect a Mavic, and I've "selected" a Spark as my equipment, with nothing connected to the phone, you're going to get the WiFi screen! Argh. If you want to fly a Mavic, you got to tell it you're connecting a Mavic.
i told you this when we first tried to cache maps,others said click on three lines[hamburger] and go to map cache.
something just told me to click on top of spark logo and wala my go4 app worked