iOS app development is the process of developing a software application for Apple's iOS operating system. The development process follows the standard software engineering practices of modularization, object orientation, and separation of concerns. App developers Ontario have to decide which programming language to use to code an iOS app. There are two popular choices: Objective-C and Swift. Objective-C is the oldest programming language in the world that is still being used today. It was originally designed for developing the NeXTSTEP operating system, and later on it was used for iOS apps too