ATIV Beam for Windows Phone is an exclusive app to the Samsung ATIV S and the Samsung ATIV Odyssey which allows you to beam content using NFC between Samsung Windows Phone and Android devices.
You can download the app directly on your Samsung Windows Phone device through the Windows Phone Store or by using the following link:
All you have to do is make sure that the 'tap+send' feature has been turned on under Settings. Samsung's ATIV Beam is only useful in sharing content between Windows Phones and Android handsets and is not required to share content between Windows Phones.