12 Need-to-Have Pregnancy Apps For Expectant Parents

Flo Period Tracker and Calendar ($49.99 a year)

Many Reddit commenters said that they'd been using Flo Period Tracker and Calendar to track their periods, making the switch to using it to track their pregnancies pretty seamless. (It's free to download, but the Pregnancy Tracker version costs extra.)

You can follow your baby's growth weekly, set a countdown, and get detailed information on newborn care. "I love flo! So many good facts and articles. I love it," writes one commenter.