I feel like my phone apps update constantly. In general, that’s a good thing, I assume. I figure they’re fixing bugs or whatever. However, I don’t run into issues very often, nowhere near the rate of updates, and nothing seems to change after the update.
Compare that to Steam games which update really infrequently and the changes are usually much more obvious.
I see a lot of the other reasons mentioned, but one I don’t: on android you are required to release updates at least every year-ish or they will completely delete your developer account and app.
Source: got that message recently for an app I made and haven’t had a reason to update.