Whenever I press the sign in button Minecraft crashes. I tried restarting my phone, reinstalling Minecraft, turning developer options on and off and joining the beta and leaving it.
When I downloaded Minecraft I could sign in fine but I wanted to leave the beta, so I uninstalled, left the beta and installed again but this problem started.
Thank you for your report!
We're actually already tracking this issue at MCPE-100100, so I will resolve and link this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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