There are plenty of basic circuits like this which don’t really need to adapt or improve over time. I like these a lot. What concerns me are those which rapidly go obsolete or lose utility.
I’m also not so sure things need to be useful forever. Many older technologies are totally obsolete and therefor not practically useful anymore. The key thing is, if this is no longer useful, how can we recycle it? How can we remove it from the world without it being a burden?
That’s probably the hardest part.
Edit: just realized a calculator is arguably a perfect candidate for being an app. I suppose my point was that it is still working well, though. A stud finder or an oven as someone else suggested is a much better example.
Most of the apps I have purchased in the past no longer honor it and have switched to a subscription because it doesn't pay for yearly maintenance.