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.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Habitica - Habitica is a free habit building and productivity application.
Any.DO - The #1 task management app used by over 11 million people globally, Any.do is your free mobile and online task manager for Android, iPhone, Web and more.
HabitBull - HabitBull
Microsoft To-Do - Task management tool
Troops - Vauxhall Troops offers loyalty discounts if the car is purchased from us and we include this in your reminder. All used cars come with 12 Months MOT as Standard, Vauxhall Troops quote a competitive fixed price for any work required.