In particular; It is forbidden to download tiles to provide offline access...
The fragmentation of Android becoming increasingly difficult to manage (in particilier since KitKat). I do not know if the project will continue
NoniGPSPlot saves the path you have traveled, locates your position in relation with other GPS points, manages alerts, and many other things.
You can find back your place at harbour after a trip on boat, the starting point of an excursion or locate your car in a huge car park,
A place of which you know the location,
To see the excursion you made,
Speed trap alert or lots of other things...
Tracks and saved points can be exported to GoogleEarth and to GPX standard.
A layer you can see the old course in the background.
Maps can be downloaded directly from the Internet if you have access from your smartphone (GoogleMap cards, YahooMap, VirtualEarth and OpenStreetMap few layers) or in advance.