I use trailforks in UK and it's second to none. Run this on the smartphone mounted on stem with a quadlock so reasonably safe (inside a protective case) for most MTBing (but take it off and put in pocket for the really black stuff). Trailforks does also run on some of the higher end Garmins but a smartphone gives me better all-round functionality and would want to carry it any way in case of emergency etc.
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