The idea that your phone could replace your payment cards has been around for several years. However, recent developments are about to make that a reality. NFC chips have been embedded in most Android phones for around two years. These allow your phone to work like a contactless card. Furthermore, Android 4.4 (also known as Kit-Kat) has supported HCE (host card emulation) for a year now. This is a change in how the security of the NFC chip is managed and means that we should expect mainstream Android banking apps to begin to support tap-to-pay in 2015. There are early adopters rolling this out in New Zealand and Australia already.
More recently, Apple announced the availability of NFC chip in the iPhone 6, as well as a payment method called ApplePay - which will allow you to pay by tapping your phone and authenticating by swiping your fingerprint. This simultaneously offers the Banks opportunities to have tap-to-pay on their iPhone apps and brings up the spectre of Apple as a competitor.