Globally, tablet sales are forecast to outstrip PC sales by 2016. While tablet customers share behaviors with PC users, there are differences across platforms that present opportunities for marketers. By 2013, over 50% of all emails are expected to be opened on mobile devices like phones and tablets, down from 36% in the first half of 2012. This poses challenges for marketers as email performs less well on these devices. Responsive design can optimize the email experience based on the device. Near field communication (NFC) is expected to enable more applications especially mobile payments, which could reach $100 billion by 2016. Mobile payments and digital wallets will continue gaining mainstream adoption through 2013 and beyond.