Police say a St John Ambulance app was crucial in rescuing an injured mountain biker near Lane Poole Reserve in Dwellingup.
The rider, a man in his 50s, was winched to safety into the RAC rescue helicopter around 6.45pm on Monday.
He was then flown to Royal Perth Hospital with non life-threatening injuries.
The man had the St John Ambulance First Responder app installed on his phone which shared his exact GPS location with paramedics and DFES.
It also provided crucial first aid tips.

Locals urged to look out for man who removed electronic monitoring device
WATCH: Whale beached at Long Point
City of Rockingham records steep increase in animal cruelty complaints related to untreated medical conditions
Accused dirt bike hoons charged by Mandurah Police
Heavy rainfall, thunderstorms to lash Mandurah down to Busselton
Drivers escape serious injury after West Pinjarra, Baldivis crashes
Police investigate stabbing of two men at Warnbro home
Shark sighted in Dawesville Channel
City of Rockingham has highest number of households receiving rent relief
