iOS 13.1 works fine on my iPhone and with Go 4 but there is a security flaw if you use third party keyboards.
Just last night I finally picked up a Mini 5 so will wait for the security patch to be released before installing on that.
As an aside 13 actually has a load of decent features and usability tweaks that make it a more significant release than is first apparent. YouTube is your friend here as I am no iOS guru.
The biggest thing is a proper folder management at last .