Puff Count: Quit Vaping Now is a vaping-cessation app with custom quit plans and daily, weekly, and monthly progress tracking.

The problem

Two problems surfaced at different points in the app’s life. Early on, the progress charts needed to plot two related data series together, and off-the-shelf charting libraries didn’t support that combination cleanly. Later, once the app had grown past 10,000 active users, Firebase’s per-read costs started eating into the app’s economics — the kind of problem that only shows up once there’s real scale to deal with.

Architecture decisions

The chart problem had a simple fix: two separate graphs, layered at adjusted opacities, stood in for a proper multi-series chart, without pulling in a heavier library to get there.

The cost problem was fixed on the client. Changing how often and how much data got fetched and displayed cut Firebase’s data-transfer costs by a large margin, without touching the backend at all. It’s a smaller, cheaper change than a caching layer, and it came from asking what the client actually needed to request in the first place.

Outcome

The app hit 30,000 downloads in its first month and reached #1 in its App Store category for quit-vaping apps. It had already scaled past 10,000 active users by the time the Firebase optimization became necessary, which points to sustained use rather than a launch-week spike.