T-Mobile free Wifi is Mobile only - will never appear on desktop or a tablet, unless the browser is emulating mobile.

*HAS* been only Gogo operated flights (Look for Connected by GoGo somewhere on the redirect page)

It did not work with Viasat flights previously. If there is something new rolling out due to AA switching to a single common portal login (vs the different login for GoGo and Viasat) - let's hope that actually happens. Though as of yesterday on a Viasat flight I didn't see the option. On the AA Entertainment site, the Wifi link on the nav menu, does show this: Free inflight Wi-Fi for eligible T-Mobile customers - Enjoy complimentary Wi-Fi, texting and streaming on most domestic flights with eligible T-Mobile plans.

https://entertainment.aa.com/wifi/

Previously it said select or some - vs MOST - so this may be a recent change as of June 1st

It for sure doesn't work on Panasonic - but alas, Panasonic WiFi barely works these days Trans-atlantic anyway so in general only get it if you truly need it