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.
Joy - Spend Happier & Build Your Savings
Habitica - Habitica is a free habit building and productivity application.
Grapefruit - An app for managing your mental health
HabitBull - HabitBull
GoodMind - AI-powered assessments & stigma-free counselling sessions
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.