On my Google Pixel 3 phone, I can never play Realms or on any Servers. "Use Cellular Data" is turned on. I have tried on a good Wi-Fi connection and with a good cellular data signal, and the only online feature that works is LAN. Usually when I click on one, it starts loading and gets to the "Loading Resources" screen, then tells me "Unable to Connect". On my tablet, a Samsung Galaxy Tab S, all of these features work on Wi-Fi (it doesn't have cellular data).
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We're tracking this issue in MCPE-36190, so this ticket is being resolved and linked as a duplicate.
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