DigitsOfPie. A Swift-based calculator for the digits of Pi (π), currently hardlimited to a maximum of 10,000 — although this can be easily changed in the storyboard slider limits. This demo uses a Machin-based Pi calculation, except that it uses the Integer package's infinite-sized integers to get as many digits as we want. It still computes the formula: pi = 4 * (4 * arccot(5) - arccot(239)). The user interface is very simple with a slider to control the number of pi digits. Calculations are performed in a background task so the slider motion is not affected during the calculations.