I finally discovered something that Yalp Store can do which Aurora Store can't: download a previously purchased app which is only available to previous buyers, but not for new ones. Yalp Store could load it when I typed in the com.foo.bar name, Aurora couldn't.
I think I'll save the APK for every app I've purchased so I don't have to deal with this again.
For all other uses, BTW, Aurora Store blows Yalp out of the water. The quality comparison isn't even close.
Related: WOW did the developer of DaTuner Pro sell out hard. I don't need to subscribe to a chromatic instrument tuner app, for fuck's sake. And I don't need skins. Give me a break.
Also related: somebody put the mandolin my hosts dug out by the air conditioner vent. Guess I'll wait a while to tune it