it's something nonstandard, so there are no approved apps, but it is only the app provided by the bank and nothing else. there used to be two, one for auth only and one for onlinebanking itself, which was optional because you could use auth to log into the web. as i understand it they merged the two apps and now only support the all-in-one app. apparently the banking features of the app can be turned off, but i could not see if that can be locked too.