Ever since the new update, the app stays on the Minecraft loading page. It goes from the mojang page then to Minecraft loading. I sat there for thirty minutes hoping it would finally start but it just stays there.
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Thank you for your report!
We're actually already tracking this issue at MCPE-45185, so we 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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I have been having the exact same issue on iOS as well. It has something to do with the update, Mojang has been silent thus far. Here is my ticket number, I included a screenshot-
https://bugs.mojang.com/browse/MCPE-45185