What this page needs
Tell me these things and I'll write it
What Roadworthy stores and where (on the phone? iCloud? a server?), whether there are accounts or sign-in, what network requests the app makes and to whom, whether there are any analytics, crash reporting or ads, how purchases work, and whether it asks for any permissions (camera, photos, location). With those answers I can write this page in the same plain-English shape as the MTG Spellbook policy.