Rоyаl Jоkеr

Royal Joker is an offline-first automotive troubleshooting app that guides you through branching diagnostic trees for OBD-II trouble codes. Follow practical checks, record measurements and notes, and narrow down likely causes with an honest confidence band. Symptom guides help you get started even without a scanner.

Explore code and PID references, vehicle-specific profiles, readiness and drive-cycle guidance, and maintenance reminders. Save and resume diagnosis sessions, then archive or export completed results as PDF repair sheets.