London virtual tours

Windsor Castle and Churchill War Rooms provide audio guides when you enter. They are loaded on devices owned by the museums/locations. You can use your own headsets.

The Imperial War Museum has an audio guide. It's perfectly fine and recommendable for folks who'd rather listen to commentary than read it, but I found the content of the audio guide extremely similar to the posted material, and I'm more a reader than a listener. The IWM is huge, and it would take a very long time to use the audio guide throughout; even reading the material is a slow process, because everything is so interesting.

These days, most major museums seem to have audio guides, and so do the big-name churches and historical sites. Sometimes they are free--covered by the entry fee; other times they cost the equivalent of a few dollars. Sometimes there is a museum-supplied device, but other times you must download the material to your smartphone or tablet. Since there are occasional problems with the download process (iffy Wi-Fi perhaps?), I'd recommend taking care of that download ahead of time if the attraction's website makes that possible and you're sure you're going to want to use the audio guide. (That is general advice, not specific to London or the UK.)

The audio guides in art museums focus on selected works, with an access number posted beside each artwork covered by the guide. A lot of art museums offer occasional--and usually-free--tours covering collection highlights or a specific aspect of the exhibition(s). It's worth checking the museum's website ahead of time to see if something will fit your schedule.

I will check out the museums for audio guides and tours once I’ve landed a place to stay for a week. Our RS London tour stayed in a Mayfair hotel, but others have suggested Bloomsbury for a return trip, and perhaps a “B&B” instead.
Thank you