I guess it's really safe cause it's open source, you can make notes on your habits but don't really do that. Its simple. Really fast. Haven't found a way to connect it to notion. In general it's a great app to track you habits. Does its job. Not more, not less.
JEFIT - Jefit is the #1 popular gym workout app for Android and iOS. Jefit allows you to manage your training routine and keep track of your workout progress easily.
Habitica - Habitica is a free habit building and productivity application.
MyFitnessPal - Track the number of calories that you consume each day with MyFitnessPal. The app also lets you create a diet and track the exercise that you complete each day whether it's walking, running or some other type of program.
HabitBull - HabitBull
Runtastic - Runtastic offers a series of fitness apps that can be used to track your running, walking, hiking, and cycling, as well as many other fitness routines. Read more about Runtastic.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.