CalcuCrvFit app for iPhone and iPad

Features include:
- Reverse Polish Notation scientific calculator
- Hundreds of built in unit conversion factors
- Stores multiple datasets,
- Datapoint storage is unlimited
- Performs the following curve fits:
* Linear Fits
* Polynomial fits up to 9th degree in standard mode
* Polynomial fits up to cubic fit for calibration mode
* Exponential fits
* Power fits
- Calculates the goodness of fit (r2 and RPD),
- Graphs the given values verses the predicted values,
- Calculates predicted values (X or Y) from the user’s input,
- Print or email reports and graphs in PDF format.
- Graphs can be printed in landscape or portrait mode
- Conversion of graph PDF document to image (bmp, jpeg, tiff, png)
- Import data from comma quote delimited files.
- Export x, y and coefficient data to a delimited file
- Contains a user guide
- Supports IOS 13 dark mode

The advantage of the curve fitting module is that it provides two modes of curve fitting: Calibration mode and Standard mode. In the Calibration Mode, an inverse prediction of X (abscissa) from Y (ordinate) is performed. As an example, if x is standard concentration values in mg/L and y is absorbance, then you can predict the concentration in mg/L from any absorbance value. The application derives X in linear and polynomials of the second and third degree by using equation roots.

The standard mode is available to fit datasets where high degree (up to 9th degree) polynomial fits are required or the Y needs to be predicted from X. Both modes provide the goodness of fit by calculating the correlation coefficient (r^2) and the relative percent difference (RPD) between the measured values and the predicted values.

The calculator is a scientific Reverse Polish Notation calculator and it can be also used to enter dataset points rapidly.