Beta Tester Device Coverage Optimizer (2D)

Mobile beta programs on TestFlight and Google Play Console live or die on one unglamorous question: out of a limited pool of willing testers, which ones actually get your app exercised across the real spread of devices and OS versions your users run? This simulator turns that into a visible greedy set-cover algorithm — a 9×10 grid of device/OS combinations is drawn top-down, a pool of candidate testers each covers a different (and overlapping) slice of that grid, and enrolling testers one at a time lights up newly-tested combinations in real time. Toggle between the greedy heuristic real QA tooling uses and plain random enrolment to see exactly how much faster coverage climbs when you enrol for coverage instead of convenience, and drag the profile-overlap and pool-size controls to see what happens when your tester pool is mostly people with the same two flagship phones, or when you have more candidates to choose from.