Much depends on the make up of your household, the arrangement of your house, and just your own personal preferences.
I think it’s quite common for people to be in the middle of something in the kitchen, either cooking or cleaning, and then want to know something that’s going on elsewhere in the house. So if you have a video doorbell or a baby monitor then putting a tablet to let you see those cameras could be very useful. The same tablet could also be used for recipes if you’re into that.
Most people don’t use it, but echo has a feature which lets it display The results of questions on a Fire tablet. So if you have an echo, that’s another option, and I think that could be combined with the video doorbell, but i’m not sure about the fire’s capabilities.
In all of these cases you’d be removing the old switch and just using the line to power the tablet.