1. Sync with other apps I already use. MyFitnessPal is the biggest example. Todo list apps or workout apps are another. I'm already entering data in these apps, so entering it again in a habit tracker is extra work.

2. Tracking negative habits. I want to tracker whether I refrained from doing something bad as frequently as I want to track doing something good.

3. As automated as possible. The biggest problem with habit trackers is if I'm too lazy to do the habit, I'm also too lazy to enter that in the tracker, so I end up with skewed data.