My "nanopremie" daughter needed a lot coming home from NICU: medications, refilling oxygen tanks, nebulizer, plus the usual bottles and poop tracking, plus we have a dog who can't be forgotten, etc.

I felt like half my time was spent standing in the kitchen wondering what I should do next. I ended up going old school, printing a checklist, grouped with different colors for things at different times of day and a column for each day of the week. Once I had a list that worked for me, I had it printed on card stock and laminated it, so I could use a dry erase marker to reuse it and have a rolling log of things like baths and poops.

That said, don't fret too much about tracking that stuff. Of all the things that have advanced infant survival, health, and wellness, apps are definitely not a major driver. If it helps your sanity, fine, but also don't get too focused on things you think will help your sanity... If that makes sense.