entity Updated 2026-07-11 Tags: Company, Mobile-Apps, Startups, Consumer-Products

Bump

Bump was the mobile app and startup co-founded by David Lieb in David Lieb on Bump, Google Photos, and Returning to YC. The original product let users exchange contact information by physically bumping phones, a behavior that made the app memorable and helped it spread after launch in 2009.

The episode treats Bump as both a success and a warning. It reached roughly 150 million installs, 10 million monthly users, and 1 to 1.5 million daily users, received Apple promotion, and created real user delight. But the main use case was too infrequent and too low-value to support a venture-scale business, making it the source case for Low-Frequency Low-Value Product.

Bump’s most important second act was discovery. When Lieb and Jake contacted the top 100 users, they found that the heaviest users were sharing photos. That Power User Discovery led to Flock, then to the camera-roll insight that shaped Google Photos after Google acquired the company.

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