I think if users really needs a walking or bike GPS app there are many GPS apps that fit the bill.
Using TomTom NDS will only stay on the streets in walking or Bike mode.
But Walking aka Hiking GPS apps and Bike GPS apps will stay on trails or foot paths.
The right GPS app for the right Job.
Just to name a couple you can find on this forum
Locus
OruxMaps
BackCountry
OsmAnd+
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