Below you will find a list of companies that Google is highlighting as approved multi-screen vendors.
By dw capital GmbH [GFDL, CC-BY-SA-3.0
or CC-BY-SA-3.0-de], via Wikimedia Commons
That means website hosts that can handle websites which need to resize to be seen across multiple and different sized screens. In other words - these are the screens found on all the devices people now use to