MHL - or mobile high-definition link enables smartphone and tablet owners to connect their device to a TV via cable. The new MHL 3.0 standard adds support for 4K video at up to 30 Hz and 7.1 surround.
MLH 3.0 announced
Some smartphones and tablets have a micro-USB connector at the bottom that supports MHL. With a MHL cable users can connect their handheld device to the TV’s MHL port or HDMI port.
MHL can connect your smartphone or tablet to the TV
MHL 3.0 has just been announced, and will take over for MHL 2.0 that capped out at 1080p (Full HD). MHL 3.0 adds support for 4K resolution at up to 30 fps, audio in 7.1 surround, and 10W power. MHL 3.0 is also backwards compatible with earlier MHL connectors.
4K might seem like overkill in a smartphone, but in a few years from now when streaming providers such as Netflix add 4K streaming a smartphone or tablet can act as a streaming intermediary for the living room TV. Wireless alternatives exist in Miracast and Airplay, but without 4K support.
MHL is developed and controlled by Nokia, Samsung, Sony, and Toshiba so expect to see 3.0 here first