Regression Testing
What is Regression Testing?
Regression testing is the systematic re-execution of tests after any code change to verify that existing functionality has not been broken. In mobile, this is critical because the platform is fragmented: a change to a payment flow might regress on an older Android version or a specific device model. A mature mobile regression suite covers: all critical user flows, edge cases for known past defects, API contract tests, accessibility checks, and performance benchmarks. Regression suites are typically run nightly or on release-candidate builds, taking 30 minutes to 4 hours depending on device coverage depth.
Related terms
Regression Testing, frequently asked questions
At minimum: on every release candidate build before submission to the App Store or Play Store. Best practice: a partial regression on every merge to main (covering critical flows), full regression overnight, and a targeted regression on any PR that touches high-risk code (payment, authentication, data persistence).
The minimum viable device matrix for regression is the top 5 device+OS combinations by your user base. A production-grade setup covers 20–50 real devices spanning OS version spread (at minimum 3 major versions back), screen sizes (small, medium, large, tablet), and manufacturer variants (Samsung One UI, Pixel stock Android, Chinese OEM on Android). Device farms make this economically viable.