This application is just a very basic calculator, nothing more, nothing less. It was my "starter project" as a developer. It is a little bit similar to the calculator of iPad / iPhone, but this is just a coincidence. There is no advertisements in this app.
In case you are looking for a more advanced calculator, I recommend you my ColorCalc calculator, which find here: https://play.google.com/store/apps/details?id=com.mesziapps.colorcalc