Split Testing (A/B Testing) with Swift

Alexander shows how a simple A/B test doubled in-app currency purchases from 2% to 4% at Badoo. Here's how to build the same testing framework in Swift.

With millions of apps competing for attention, companies like Badoo run multiple split tests simultaneously to validate features. This article walks through building a client-side A/B testing framework in Swift, complete with persistent storage and analytics integration.

Key Takeaways

• Build client-side Swift A/B testing without external servers or dependencies
• Protocol-based architecture uses enums, UserDefaults, and analytics integration
• Real test doubled purchase rate: 2% baseline to 4% with optimized difficulty
• Framework designed for sub-1-minute setup time for new experiments

The full GitHub implementation reveals how Badoo manages multiple simultaneous tests with persistent user grouping.