Most habit apps track you alone , and quietly die after week 2. ChallengeUp makes consistency social: join group challenges, post daily photo/video proof your teammates actually see, and build streaks together. What's different: your Challenge Score , a public trust score earned by finishing what you start (completion rate, peer ratings, check-in consistency). Quit and it drops. Plus GPS-based challenges near you for meeting doers in real life. Free, English & German.