I built "The Great Lock-In" app (currently trending on the App Store)

Over the past month, there’s been a trend on social media called The Great Lock-In (running Sep–Dec). I decided to turn it into an app: The Great Lock-In on the App Store .

The idea is simple: it helps you participate in the lock-in challenge by tracking progress, building streaks, and staying consistent. I built it as a side project, and to my surprise it’s now trending on the App Store.

Would love feedback from the HN community - especially around onboarding, retention mechanics, and whether this kind of lightweight “social trend → app” approach has legs beyond the initial hype.