Mmsaws,
Depends on where a person lives and what you mean by plotter.
If a person lives (like you) on the coast or great lakes, then apps that use the free NOAA charts are available. Many more choices then.
On inland lakes, sometimes the only choice is Navionics, as they have done a great job charting inland lakes.
The downside of Navionics is that it is NOT a true charting app. It's really a map viewer that shows your position and speed. They keep the feature set low to not make the REAL customers of their charting mad (like Lowrance and Raymarine).
I would look at iNavX. We use it on an iPad but it runs on android too. Many more chart plotter features there. Much better route planning, projected course lines, and it can draw the chart course up.
It makes a great backup or Nav at a second station. But I'd recommend not using is as primary electronic aid. too many things to go wrong.