OLD Derivative Calc is a free Android application that offers a comprehensive set of tools for calculus enthusiasts. Developed by Ivan Petuhov, this app provides users with a range of features to help them solve derivative calculus problems.

The app's interface is user-friendly and easy to navigate, which makes it ideal for both students and professionals. Users can input functions and calculate their derivatives with ease. Additionally, the app provides step-by-step solutions to the problems, making it an excellent learning tool.

Overall, OLD Derivative Calc is an excellent app for anyone looking to solve derivative calculus problems. Its comprehensive set of features and user-friendly interface make it an excellent choice for both students and professionals alike.