MashON guide
A Ghost Mash replays a recorded activity along its route so you can compare your current effort with a past performance while cycling, running, or walking.
Updated September 27, 2026.
Your recorded activity becomes a moving ghost. Follow the route and compare your performance with the original activity. A Ghost Mash is a personal replay; live group Mashes and friend challenges are separate ways to use MashON.
During Ghost creation, choose an activity from Apple Fitness, Strava, or Saved Activities. Apple Fitness and Strava activities need a saved outdoor GPS route. Review the activity before selecting it for your Mash.
Yes. Import a recorded GPX activity into Saved Activities, then choose it when creating your Ghost Mash. Ghost replay needs a timestamp for every track point and valid chronological timing. A GPX file containing only route geometry cannot replay the original pace.
Use Edit or Trim Activity in Saved Activities to remove part of the start or end by time or distance. Review the map before saving. MashON keeps the untrimmed original so you can revert your changes.
Cloud Sync is off by default. Saved Activities stay on your device unless you enable Cloud Sync in App Settings. Enabling it uploads activity files, including any retained original, to your account for syncing across signed-in devices. These files can contain precise routes and fitness measurements.
In Ghost and Challenge modes, Watch pages show distance and time gaps, whether the ghost is ahead or behind, route progress, and available route accuracy. Learn more in the Apple Watch guide.
Choose the activity and start your Mash on iPhone. GPS quality and the recorded route affect the comparison. MashON is not an emergency or collision-avoidance system; stop safely before interacting with your screen.
MashON is available for iPhone and Apple Watch.
Download on the App Store
