I've started to use the Commonwealth Bank mobile app for a lot of the little management tasks for my accounts, just because it lets me log in with a PIN instead of a username and password. It's much more convenient and faster than the website. Of course, it's also a bit more annoying to have to use the small touch screen than a mouse and keyboard, so it's a trade-off. So far, though, the convenience of the login is beating the usability of the computer desktop.
The desktop website is deliberately written to prevent any browser password manager from remembering your password. I don't memorise my passwords, myself, because they're stronger if they're unique, randomly-generated and long. For me, this makes its usability much lower.
I think, together, this says something about security and convenience, in that people will choose greater convenience over security when they can. I know I have.
Mokalus of Borg
PS - Except for the complicated, unmemorisable passwords.
PPS - I've made sure to stick to that.