The calculator will request the following input:
Reynolds’ Number, Pipe Diameter and the Pipe Surface Roughness
The calculated result produces the following output:
Relative Roughness
Darcy Friction Factor
Fanning Friction Factor
There are two different equations that the calculator uses based on user choice,
You can choose from either CHURCHILL EQUATION or COLEBROOK-WHITE EQUATION
The App will do iteration to compute the friction factor if the Colebrook-White equation is used. 
Both equations produce a close estimate and would save time instead of looking up charts.
The App accepts input in two different units, SI Units and US Units. There is a small database for different pipe materials that include values for Surface Roughness taken from literature,
The material list is below:
Copper, Glass, Plastic, Brass, Iron, Steel, Concrete, Rubber
Download & Purchase information
This application has two versions:
A free version that includes a banner advert and requires internet connection you can download it from the Google play store
The Second version has no adverts and doesn’t require internet connection and is available for purchase from the Google Play store using the link below
Purchase Now
System Requirement
Android operating system (2 and up)