There's hardly any doubt at this point that Apple will roll out its Touch ID fingerprint reader to all iOS devices sooner than later. As you know, the sophisticated fingerprint sensor debuted last September as an iPhone 5s exclusive and is based on technologies from Israeli startup AuthenTec that got acquired by Apple for the reported $356 million in the summer of 2012.
While Apple was originally rumored to bring fingerprint-scanning to its tablet lineup, its manufacturing partner TSMC was unable to build enough of the sensors for the iPhone 5s alone, causing handset shortages after the launch.
Notable mentions of Touch ID for the iPad have been discovered in the iOS code, indicating an upcoming iPad hardware refresh might include the fingerprint sensor. It's worth pointing out that iOS code frequently contains placeholders and hooks for unreleased features that never see the light of day. This is not the first time Apple's code references Touch ID for iPads but we felt you should know about this...