Ticket inspectors should not be checking commuters addresses on their private banking apps, so Victoria's privacy commissioner is considering an official review of the "ridiculous" practice.
According to reports from commuters, ticket inspectors have navigated through their phone banking apps to check contact details and to verify identities when issuing a fine.
Hospitality worker Brittani Clayton says she could not find anything with both her name and current address after being caught without a valid ticket on a tram.
"He saw my CommBank card while I'm flicking through all my stuff and told me I can get my address off the app," she told AAP.
"While I was holding my phone, he was the one who pressed on the screen and showed me how to get it."
She said he also asked to see where "home" was on her Uber app.
Another commuter, who did not want to be named, says an inspector snatched the phone out of his hands after he logged into his bank app.
Other passengers say ticket inspectors have suggested verifying their address through banking apps but did not touch their phone.
Privacy Commissioner David Watts says the demand is "simply ridiculous" and he will consider an audit of the alleged practice.
He urged people who have encountered the demand to contact his office.
"It's unfair and unreasonably intrusive and a breach of privacy," Mr Watts told AAP.
It is understood ticket inspectors can look at utility bills and "viewable documents" on a passenger's personal phone to verify identity but they are not permitted to touch or take control of the phone.
As a last resort, the police may be called to verify identity.
Yarra Trams denies the ticket inspectors they employ handle phones.
"Passengers may be asked to verify their identity. Our officers do not ask passengers to access their bank accounts," it tweeted.
Public Transport Victoria said in a statement: "PTV is sorry to hear about this passenger's experience and the incident is being investigated."
Bank customers are encouraged to change their password if concerned about account security.
"Customers should never give anyone their CommBank app or NetBank logins or passwords," Commonwealth Bank said in a statement to AAP.