i need one that doesnt depend on me being on line, im not sure if one exists
the only thing I would think data connection is for is so your track can be mapped onto a map.
As above I have a Note 4 and its built in. They are good, for me gets me off my backside.
Rocks if there free just give them a go. You may be surprised.
If its calories burned many walking or excersice apps will show you distance, but not steps.
See below for a pedometer result.
Thats in green.
Map my ride, map and results. ( Free app)