For some people, mobile is a luxury. For others, mobile is a necessity. So, it is quite challenging for mobile app developers to create apps that work on multiple platforms.
There are a lot of opportunities for new developers. The newest app code rests on the concept of writing code once and runs it anywhere (WORA). The app developer writes code which can run on multiple platforms. The purpose of cross-platform mobile development tools is to save long-hours of coding. The app developers can reuse the code and run on iOS, Windows, and Android devices.