Retail App: Payment Flow Broken by iOS Update
Challenge:
A retail client's iOS app used a payment library that relied on a UIWebView-based authentication flow. Apple deprecated UIWebView in iOS 14 and removed it entirely in iOS 15. Users on iOS 15 could not complete the checkout.
The Solution:
We identified the failing component during OS beta testing and migrated the payment flow to WKWebView, using the payment gateway's updated authentication implementation. The fix was deployed through TestFlight for internal verification before the public release. The client's iOS 15 users received the working checkout before the OS update reached the majority of their user base.
Results:
- Fix completed and released in the two-week window between iOS 15's public announcement and its general availability
- Zero user-facing downtime on checkout resulted from the update
Fintech App: Authentication Library CVE Required Emergency Patch
Challenge:
A security scan identified a known CVE in the version of an OAuth library used by a fintech client's Android app. The vulnerability allowed token interception under specific network conditions. The library maintainer had published a patched version 60 days earlier.
The Solution:
We updated the library version and audited the token handling flow against the updated implementation. We ran regression testing across Android 10 through 14. The update deployed through Google Play's staged rollout, which let us monitor crash rates in a 10 percent cohort before expanding to full release.
Results:
- Patched version reached 100% of active users within 72 hours of the staged rollout completing
- No token interception incidents were reported before or after the patch
