Today is the day that Google are changing their ranking algorithm to favour web sites that are deemed to be mobile-friendly. This is a reaction to the fact that mobile web traffic has now surpassed that of desktop computers.
Specifically, Google are looking for sites to be responsive, with appropriately sized and spaced content that fits within the screens of smaller mobile devices.
Helpfully (and uncharacteristically) Google have provided a test engine where you can enter you or your clients’ URLs and see whether they are deemed to be mobile-friendly: https://www.google.co.uk/webmasters/tools/mobile-friendly/.
Our advice is not to panic about these changes but it’s definitely a good idea to make your site mobile friendly for the benefit of users and search engine rankings alike.
In most cases it can be pretty easy to resolve problems so do contact us if your site gets a poor test results.