I agree that trying to sign up elderly listeners would be an excellent idea. You will probably need a pretty strong technical support crew for them, because they in general won't have our comfort level with computers.

My father has been working to keep some older relatives able to use computers, but there are lots of challenges. A couple of points I can offer from his experience: - Tablets are probably easier use, especially if you spent some effort making a specific app. - Reliable always on internet is not necessarily a given. - Even if they have good internet, they may not have a wireless network