I am having the same issue on 3 different Android devices trying to connect to the same realm from multiple networks.
Played last night at home without issue on two devices (my tablet and my daughter's phone, both working together)
This morning loading hangs on that purple screen on both devices, so then I tried connecting a few times from my phonr while at work, on the work network which has worked in the past and it's failing with the same purple screen.
Also I've tried downloading the realm, it allows the download, but after clicking 'let's go!' no world has been saved locally, tries this on my tablet and phone as well with the same result.
I am having a 'disconnected from server' error when my daughter and I try to play together in our private realm, we both get booted, but if only one of us us playing everything works fine.
I am also experiencing this bug.
The progress bar increases, but at the one only one item from a stack is transfered. I tried multiple chests and rebooting my tablet to verify it was persistent, it is.