Basically that article gave a couple of points to be cautious about. But none are tied directly to the security of the data connection or application. Basically the biggest potential problem is if someone gets your phone. My bank doesn't have a dedicated app, but I would hope you would still need to log in with a dedicated app. If any person can pick up your phone and enter the app without needing to put in any password, then yeah, it is a security risk. You need to either pass lock the phone, or make sure the app/online site requires a passwork everytime you login.