From a business perspective, how we target our audience has evolved to reflect the changes in technology and now much of marketing is done online. Over 20% of website traffic now comes from mobile devises such as smartphones and tablets so it's important that your website is mobile optimised. This means re-ordering how your website displays on a small screen, for example a mobile screen can convert your website view to a single column display. A simple way to check this is to look at your website from your mobile phone.
Just don't do it last thing at night or first thing in the morning.