UncertaintyCalc app for iPhone and iPad

UncertaintyCalc calculates the measurement uncertainty according to the Guide to the Expression of Uncertainty in Measurement (GUM). Users can input up to three input quantities with their respective uncertainty contributions. For each input quantity, specify the numerical value, the statistical distribution (normal or rectangular), and the type of evaluation (GUM Type A or B).

The app displays the uncertainty budget as well as the final measurement result in the format recommended by GUM: y = m +/- U , where:

• y : Measurement quantity
• m : Best estimate
• U : Expanded measurement uncertainty

Users can select a coverage factor k to reflect the confidence level of the uncertainty interval.

In this version, the measurement model is based on the addition of input quantities only, making it suitable for the evaluation of direct measurements of electrical voltage, current, and resistance using a multimeter.