zaFin is a project which builds up slowly over time, showcasing some of the more useful financial calculators like PAYE and Mortgage Calculator for example.
As time and space allow, these tools will be transformed and ported onto various platforms, such as the zaFin for BlackBerry project.
These tools are being provided free of charge to the general public. I hope you find them useful in that they help you make some informed, rational decisions regarding your finances based on numbers and not just on marketing and/or emotions.
So always use an actuary, financial or tax consultant before making a decision regarding your finances. These applications provide you with some rounded calculations based on data and estimates which may or may not be erroneous at the time. It's being provided in good faith, at no cost to you, and as such you use them entirely at your own risk.