Well it seems to work well on 16yo Lagavulin with Android 7.0 … but I couldn’t login to existing account… having transferred the password over USB to double check, I’m not sure what’s occurring that’s stopping it.
edit: Using a new invitation code (thanks @JPL) and creating a new account, it just works™!
Simple download and run, is ideal.
The only issue I saw from the functioning otherwise was that copying the invitation code, doesn’t present a pop that suggests the code has been copied to clipboard, which is always useful to see… but that is the website, so full marks for the Authenticator itself.
The other thought was the typing of a long password on the phone is a pina; so, hoping in future to be able to trigger a new account with fingerprint… given there’s no difference with a plain text password stored or typed in for real security of that.