The real trick is finding that one thing that does the job you want it to.
For years I'd been looking for an app to tune my guitar with. All the ones I could find would just play a fixed set of 6 notes, then you have to tune it by ear. Half the screen was taken up by ads.
Then some random thread pointed me towards an app called Tuner on FDroid. This uses your phone's microphone to listen to any note you play, then it shows the note on a musical stave, and the bottom half of the screen is actually a frequency chart which shows the bounds of the note and where the microphone hears it. You can actually see the bending of the note from when you pluck the string and raise the pitch slightly to where it rings on its own, and decide where to tune to fit as you like. You can also tune to any sort of alternate tuning that your heart desires. An in-line tuner is probably still better (in particular against background noise) but this was the kind of thing that should have been widely available from the start in phones.
But such apps are not advertised, you have to stumble across them, and there's no easy way to sift through all the shit to find them.
The real problem is in how everything is monetised. Most of these apps and services are very cheaply and easily made, and as such there are people who want to make them, purely on a whim. But the good ones get drowned out by the money-grabbing ventures that don't actually fulfill objectives. Somewhere around the 00's the ethos of software development changed from being focused on the user experience to being focused on how the publisher could extract revenue from users, and that is a monumentous shame.