My grandma can't be convinced to use a laptop or a smartphone so every evening she goes through her analog albums. Whenever I visit her, she always wants to see the up to date digital photos/videos of our family that I have and tells me she wishes she could see all of these more often. Especially vidoes, since you can;t print them.

I came up with an idea of buying a tablet for her and installing a very simple, one-task-oriented Linux distro (or maybe there are some other options?). I need some step by step instructions what to do to achieve this: a tablet that displays a photo/video gallery with directories divided into photos/videos/years and dirs dictated by tags (I will manually tag items for, for example, herself, her son, her grandson etc, before giving the tablet to her), without anything else in view. Well, maybe except for like a battery level (should I add smth more to this short list?).

I have a few TB of data she may want, so maybe in the future I would want it to display stuff from my not-yet-created NAS, so it would be nice if the tablet could connect to a wifi. Talking about storage, I guess I would put in there a 1TB microSD. I heard that's the current upper limit (at a reasonable price, maybe there are some xTB microSDs but I haven't heard about them).

Once again, it's a fresh idea and I'm looking for some guidance. It has to be simplistic as hell for her to use that. Turn the tablet on and off (no login or anything), and display a gallery. And maybe the ability to add items to favourites. Thanks in advance, it's really important for me.