Each iOS device has a Calculator module in the Control Center that can be activated from the Control Center settings. This calculator module is quite limited and only allows users to launch the calculator app quickly, regardless of whether they are in the app, on the lock screen, or on the home screen. The user can also press the Calculator button that reveals the Calculator widget where users can touch the 'Copy last results' option to copy the results of their last calculation.
The newly released CCCalc setting makes the Calculator Control Center module much more useful by converting it from a simple Calculator shortcut into a complete Calculator application that can be used to do all kinds of calculations. The CCCalc widget in the Control Center offers all kinds of calculator functions, including +, -, *,%, and / and more.
Users can quickly access the CCCalc module by accessing the Control Center screen and then pressing the Calculator button.
If you don't have a Calculator button in the Control Center, you can activate it by going to Settings -> Control Center -> Adjust Control -> Scroll down and Touchez the green '+' button next to the Calculator.
You can download a simple but very useful CCCalc setting on your released device for free. It is available in the developer's Github repository. To download settings simply add "https://gilesgc.github.io/repo" to your Cydia or Sileo source and install it.