Flyover
Finish a run, open it in Aera, and tap Flyover. The camera lifts off and flies your route back over the real ground: the park, the river, the hill you walked up. Your pace, heart rate and elevation play along underneath, and you can scrub to any moment or switch between them.

A Flyover of any run from the last seven days is free. Older runs are part of Premium, and they stay visible so you can see what is there. There is no account to make.
An iPhone, and a run with a GPS route saved in Apple Health. Runs recorded on an Apple Watch save one. Aera's own watch app records on its own, without your phone, and pauses when you stop.
The replay follows the route your watch recorded, so it is only as exact as that GPS track. Health numbers are worked out on your iPhone and stay there. Every number in the app opens a short note on how it was calculated and where it stops being reliable.