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.
HubSpot Marketing Hub - HubSpot is a cloud-based inbound marketing software that allows businesses to transform the way that they market online.
Habitica - Habitica is a free habit building and productivity application.
ShortStack - Shortstack is a website that allows you to create viral online events for your social media followers or other online audience.
HabitBull - HabitBull
Woobox - Woobox helps you easily create powerful contests, sweepstakes, coupons, and more to grow your fans...
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.