We get this question all the time and we're here to shed some light on the answers from reputable websites.
Windshield phone mounts are illegal in 34 states, meaning that traditional methods (not Hudly) for putting your phone on your windshield are illegal in 34 states.
Drivers in: Alaska, Arizona, Colorado, Hawii, Illinois, Indiana, Maine, and Nevada, have to ensure that there are no posters, signs, or other types of NON-TRANSPARENT material blocking their view. They are allowed to have transparent or semi-transparent things on the windshield as long as it doesn't prohibit them from seeing through the glass entirely.
Placement rules: California, Florida, Minnesota, and Ohio say that GPS systems, toll payment systems, and other safety monitoring equipment are allowed but need to be placed at the bottom of the windshield.
Currently, all 50 US states and Canada have no laws that prohibit the use of any Hudly products.