Feedback from farmers and consultants pointed to the need for a mobile app to aid planning of lime application. Such an app needed to estimate responses to managing soil acidity with lime, in an easy-to-use interface. The iLime app was developed using cycles of drafting–feedback–redrafting to ensure that what has been produced will be of use and valued by the target audience of farmers and consultants.

iLime implements the Optlime spreadsheet model in an easy-to-use app. Users can generate results with just a few selections and may specify options to suit their circumstances.

The Optlime spreadsheet models the main factors related to soil acidity. It was developed as part of the 'Time to Lime' research programme, 1996—2001, using established principles of soil acidity and results from field and laboratory experiments carried out in WA. It has been tested against subsequent research data and was thoroughly reviewed in 2008. iLime has also been tested using data collected over the past 10 years (paper in preparation).

Optlime was originally developed by Andrew Sandison and Andrew Bathgate with refinement and spreadsheet design by Michael O'Connell. Contributors: Bill Porter, Perry Dolling, Amanda Miller, Lorrelle Lightfoot, Mark Whitten, Eugene Diatlof, Andrew Rate, Zed Rengel, Nicole Glenn, Caixan Tang and Chris Gazey and James Fisher. Concept & equations in the 2008 version: Bill Bowden, Craig Scanlan and Chris Gazey.