3D Graphing Calculator is a free Android application developed by SwanTaleTech. It is a user-friendly tool that allows you to plot functions and surfaces in 3D of type f(x,y). The app is designed to be easy to use and provides a range of features to help you generate 3D graphs with ease.

To plot a function, all you need to do is type the equation of your function in the provided field and click on OK. The app will then generate a 3D graph of the function. You can then rotate, translate, and zoom into your 3D graph to inspect it. Additionally, in the settings tab, you can specify the axis size to generate the graph within your required interval.

Upgrading to the full version of the app will remove ads and allow you to export your 3D graph to OBJ format. The export feature is simple to use; just click on the export button and your graph will be exported to OBJ format which can be easily viewed in most 3D modeling software.

Overall, 3D Graphing Calculator is a fantastic app for anyone looking to plot functions and surfaces in 3D. Its user-friendly interface and range of features make it a must-have for anyone interested in 3D graphing.