TSMC is expected to produce 120 million Touch IDs throughout 2014, representing 233% growth since last year. These shipments will include the next generation iPhones, as well as the iPad Air 2 and the iPad Mini 3. The first batch of Touch IDs will start shipping in early July, according to the report. In addition, the report claims that the next generation Touch IDs will improved the sensor module's durability.
iOS 8 will be bringing the ability for developers implement Touch ID into their applications, letting users sign-in to third party applications without entering a password. This could also be expanded to mobile payments in the future and apps like PayPal have been working on bringing Touch ID to the app for iOS 8.
Apple has been rumored to launch their own mobile payment service sometime in the next year or two, so it would make sense to have their entire iOS lineup compatible with Touch ID