What is this application's usage on my Android?
The MotLauncher is the stock launcher for Android KiKat on Motorola devices. It's used to provide access to apps and settings. The launcher is a GUI to the operating system. It allows you to configure various aspects through the icons. There are plenty launchers on Google Play Store and you can install almost any of them.
Browse the store to download others: https://play.google.com/store/search?q=launcher&c=apps&docType=1&sp=CAFiCgoIbGF1bmNoZXJ6AhgAigECCAE%3D