My husband and I just returned from a fabulous first trip to Italy. Amazing country. HOWEVER - we found the Venezia Unica "card" - printed and downloaded pre trip - was a rip-off.
One of our transit passes (worth 40 euro) QR code didn't work. The recommendation of the staff - who saw me download it, try it in 5 machines and could see the app was valid and counting down - was to "climb under the turnstiles and hope I wasn't checked on any of the ferries". They wouldn't let us speak to a supervisor and wouldn't offer any solutions. "We can not help you because you are using the app". I still haven't heard back from the company.
We never found the canal tour boat company and never heard from the company.
The Theatre was closed to tours during our time there.
We would have been better to just purchase the individual ticket to the Doge Palace.
My advice: enjoy Venice without the Venezia Unica card.
I think most people here wouldn't recommend the Unica card, so you're preaching to the choir. The 1, 2, or3 day vaporetto card is more likely to be of value, but even there one has to evaluate how many boat trips they were likely to need.
Thanks for the warning. There are scads of readers of this forum who will benefit, those who post are a minority.
I would contact your credit card company to see if you could at least get a 40 Euro credit for the transit pass that never worked.