There was a download of APFill 4.4 on the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The program lies within Office Tools, more precisely Calculators. The program's installer is commonly called APFill.exe. We recommend checking the downloaded files with any free antivirus. The most popular version among APFill users is 4.4. This software was originally designed by AVPSoft.com.
From the developer:
Ink usage is usually described by the printer manufactures as so many pages of A4 using 5% coverage. This software helps you determine the amount of ink coverage on page before printing expressed as a percentage. So you will be able to estimate cost price of the page to a first approximation
You may want to check out more software, such as Free QuData Calculator, iUnit or iCalc, which might be related to APFill.