I recently downloaded Zwift for my Pixel 3. I use a Tacx Neo with a Wahoo Tickr HRM with everything paired via Bluetooth.
I recently did a 90min group ride in Watopia, with 2k plus users in-world. My experience running Zwift on my Pixel3 was surprisingly smooth (no Bluetooth dropout, no dropped framerates).
Screen size was the only downside I noticed.
Koodos to the developers. Ride-on!