I tried a couple, but deleted them. I didn’t love the privacy policy statements. I tried one called ShotTracker and it has a better privacy policy, but not much other utility for what I do, so I don’t plan to keep up with it either. (You can choose from a handful of injection sites, keep your inventory and link vials so that all of the vials in a kit have the same info (like actual mg and reconstitution), can enter any pep you want, etc. and it’s a 1-time fee not a subscription.)
I just use the GLP1 plotter spreadsheet for long half-life stuff and log everything in a separate calendar on my phone, just for a record. I don’t need or use reminders, so the spreadsheet is my jam.
Here’s a screenshot with part of the privacy policy for an app called PepTracker. My advice is to just review the privacy policies on the developer sites and make sure you’re comfortable putting all of your grey market substances in them.