There are a couple of apps out there! Although my experience was that I didn't really have a need for the data when all was said and done. Maybe I should have picked up knitting..
(Then again, I usually use a sleep tracker, and aside from a quick glance in the morning, never ever look at the data again. But I figure baby tracking has a decent amount of overhead, and parents are already overworked and overtired enough as it is...)
Tracking is genuinely useful though when you’ve noticed something and are trying to gather evidence of a pattern to bring to a healthcare professional - for example around sleeping or feeding.