ski tracking accuracy

Today i recorded my day on the epix2 on my ski trip

all these years i use my phone and the application ski tracks which also i did today

The two results fron the epix and the phone are quite different

On the watch  it recorded elapsed time 4:01:06 hours

 with 11.2 km descent and max speed 58.2km avg speed 25.8km

On the smartphone elapsed time5.05.04

14.6km descent

max speed 60.1 avg 23.5km

Quite a diference on elapsed time and ascent ski distance

Which should i trust more???