Almost every OEM has its own specific set of branded applications. HTC has its Sense UI and related apps and Samsung has TouchWiz, which makes running KitKat on the International Galaxy S III "impossible." These applications can be used with other ROMs, but they requiring some work. On XDA, we call it porting and you can find many of such applications located in various forums.

With PortedAPP by XDA Forum Member APP-Maker, you can now use OEM-specific applications on other devices without effort. All you need to do is run the app, select an OEM, and download your desired application, ready to install. The current list of supported apps includes those from OEMs like Samsung, Sony, and Nokia. CyanogenMod- and MIUI-specific apps are also included. Root is not required, and every application runs flawlessly on most devices. Essentially, this application a database with applications ported from other devices/ROMs.

You can find out more by taking a trip over to the application thread.