Very useful!

Core Coders apps are very good. Battery efficient; run it all day and use less than 25% of your battery. I use the app a little bit for biking but a lot for hiking (I wish they would adapt this app for hiking). Good and interesting dsiplays, integrationwith the Health app. Only complaints are there are occasional disparities between the distance shown on the maps and show on the displays by up to 10%, and that the altitudes remain GPS based instead of being linked to the altimeters in the 6 and 7 phones.

RyderDA about Bike Tracks, v1.2.4