Appstem is a company that specializes in IT solutions for mobile and desktop operating systems. This American firm employs skilled computer programmers who are familiar with open source scripts and codes that define most applications on the World Wide Web. For example, Java is without a doubt the most important syntax in the development and management of apps for the Android platform. This programming language can be easily written in virtual design suites that don't cost much to download. For example, the Android Studio software is loaded with powerful tools that let developers synthesize and validate source code. Hosted on a cloud network, Google Firebase is another reliable program that has many development tools. Appstem goes to great lengths to check the back ends of Android apps that are supposed to function properly on smartphones by Samsung, LG, HTC and other brands. The touch-screen interface of apps must also be checked and optimized for different hardware.