Very annoying and dysfunctional
The Alilaguna pass was clear that you needed to obtain a paper ticket before validating it at a ticket office at the airport. Super easy to do. The vaporetto pass, however, stated it could be used with the downloaded barcode. We tried several times to use it and the screen message stated it was expired. At a transport kiosk a helpful staff member told us we needed a paper ticket as the barcodes do not work. We were able to download a paper ticket at a ticket machine after a day of fussing about.
It makes no sense to have barcodes that do not work at transport gates and require a paper ticket too. In addition, the app charges a service fee to download a useless barcode when you can easily buy tickets up to seven days upon arrival with no service charge.
In addition to these issues, the back button on the app doesn’t work well at all (iPhone 15).