I downloaded this app for 8 yuan, and the interface design is extremely minimalist—just fill in your name and emergency contact email, then check in daily. If you miss two days in a row, the system sends an email to the contact.

It seems nothing special, but this creative app has recently gone completely viral. In half a year, it went from 0 to a valuation of 10 million, with a cost of only 1,500 yuan. It ranks first on the App Store paid app chart, with explosive downloads. How did it achieve this?

Simple features, strong conceptual impact, combined with social media dissemination—just a few elements stacking together can trigger viral growth. Users share out of curiosity, which brings in new users, turning the growth curve into an exponential. From this case, the logic of viral hits in Web2 apps is quite clear: identify pain points, have strong virality, low cost, and quick conversion. Small but refined creative apps still hold huge potential.