It is safe to assume that all/most of the major sites/museums in Rome/Florence/Venice will have audio guides available to use/rent? Planning a trip in May and will want to see whether I will need to look for listening guide apps. I know that the Fenice Opera House's website indicates a preference for using their app, since their audio guides are limited. (I assume that hygienically, others are moving toward apps, but it's difficult to get current information!)
I am also considering whether to book guided tours or visit on my own with an audio guide. I prefer going on my own, but may consider tours for the Colosseum and the Vatican, for instance.
I think the RS audio guides sound good, but 1) he doesn't do guides for everything I want to visit, and 2) some exhibits change over time (and likely during pandemic times).
If you have found audio guide apps that you like, I'd love to hear about that as well. Thanks!