We've gained experience in developing software since 1990, initially in Pascal. For the past 19 years, we have been using object oriented programming with the Objective-C language, with the help of NEXTSTEP/OPENSTEP operating system, and with its most advanced development tools, and now with Apple's macOS operating system. More details can be found here. We’ve also leveraged our knowledge in OS X and Cocoa to tackle development of iOS applications as well. SL Notifier is our first iOS application on the App Store.
We have also developed and worked on a few software for the Newton platform, specifically the Apple MessagePad.