I, using iOS12 public beta, cannot get a trail to record. It starts, shows location on the map, but does not record any stats. At the end of the trail, can select end, but as there is no details to record, it assumes that I have not gone anywhere.
Obviously its a beta iOS, but just an case anyone else is thinking of upgrading…
OK - A quick update. After trying several settings with the iPhone, it appears that tracking does not work in the app if WiFi is either switched off or you are in an area where there is no WiFi. As soon as the iPhone gets a signal, then tracking starts again. Not very useful when you are out on the moors, but then at least I have isolated the issue.