Have you got a Samsung Galaxy S3?
Samsung S3 have lots of enthusiastic fans, they like all kinds of accessories of S3
I just want recommend a HDMI dock for you.
Samsung Galaxy S3 HDMI docking station
It have HDMI function also can support Connect external USB devices ( such as : mouse , keyboard , etc.) to the DOCK USB interface.
Samsung GALAXY S3,Samsung GALAXY S4,Samsung GALAXY NOTE2