Mobile apps are software applications developed specifically for use on small, wireless computing devices, such as tablets and smartphones and tablets.
Usually these apps need to be installed on the device from a third-party provided such as Apple's App Store (iPhones and iPads) or Google Play for Android smartphones and tablets.
Mobile apps development is a specialised skills in terms of both design and well as coding. Often developers also specialise is either iOS or Android development. In addition, new technologies like React-Native enable developers to build in a hybrid style language that can be used across both iOS and Android platforms.