If you're looking for some ways to chart and visualize your data in an Android app, here's a library that might make your life a bit easier: MPAndroidChart.
It does exactly what it sounds like: provides a hefty set of tools to help you create slick-looking representations of your data - line and bar graphs, pie charts, and so on - along with the options you'd need to interact with them. Something like this, for example:
(Source: MPAndroidChart GitHub)
Despite the disappointingly low revenue of Quarter 1 above, that's pretty cool. There's also an example app on the Play Store if you want to get a feel for what it all looks like - that's really the point of all this anyways, says creator Philip J. - and a demo video, too: