User experience signals to log for mobile observability

The green dashboard fallacy Every mobile engineer has experienced this scenario in some form or another: your backend health is green, your crash free rate is at 99.9%. Yet, App Store reviews are flooding in about the app being "slow" or about a broken experience users encountered. Here's the problem: Mobile apps fail in ways traditional observability tools can't detect and dashboards can't see. Teams log for the disaster (the crash) but they're blind to the friction (the jank). The approach is reactive, fragmented, and heavily sampled. To build a high performance mobile app in 2026, you need to log the signals that explain how the app behaves on a real device. Your strategy should shine a light on the mobile-specific blind spots that servers simply don't have. In this three-part series, we'll unpack the most important signals mobile teams should be capturing, starting with user experience (UX) signals. User experience (UX) signals The first blindspot in mobile observability is that us