Poopmaster allows you to track your bowel movements. Simply tell it when you're in the bathroom and optionally log additional meta data to help you track how well you're doing.
This app is intended primarily for those suffering from ulcerative colitis or Crohn's disease, but others may find it useful as well.
This app is donationware - full functionality is provided for free! However, if you find it useful, it is highly appreciated if you would use the in app purchase functionality to make a donation to support its development!