I've been using the app ‘Smart Peptide Tracker.’ It seems to be updated frequently, and I liked the features enough to pay for the full version. It helps keep track of multiple peptides, and I've also started logging supplements there as well. I'm poking my rat 3–4 times a day, so keeping track of protocol schedules and dosages can get tricky, but the app makes it simple and helps prevent potential mistakes. It also includes an injection site tracker, which makes it easier to rotate sites when needed.
Hope this helps!