This document discusses pretotyping as an alternative to app prototyping for validating mobile app ideas. Pretotyping involves creating mockups of an app's title, icon, description and screenshots to test with users before full development. It recommends using A/B testing platforms to compare different pretotype versions and elements like title, description and visuals to decide which idea or features to pursue. The document outlines how A/B testing works with pretotyping and common mistakes to avoid like testing for too short a time, with too small changes or misinterpreting results.