Over 50% of searches are now carried out on mobiles.
Mobiles present significant challenges to web pages as they come in a variety of formats and resolutions, are generally small and often download off slower data connections.
Mobiles are considered more important in marketing because the "prospect" is more likely to be near.
Google provide a simple tool to test for mobile friendliness. Mobile Friendly Test
Solutions to being mobile friendly can include have separate mobile only sites, using AMP or similar and applying Responsive Web Designs to a website.
Good practice like picking up on issues in the Technical Audit go along way to improving mobile issues.
Google Ads can specifically target mobiles in a local area.
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