"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Apple Releases iOS 9.3.4 With Important Security Fix [Update: Jailbreak Patched]
iOS 9.3.4 is available immediately via an over-the-air download on all devices running iOS 9.
According to Apple's release notes, iOS 9.3.4 provides "an important security update" and is recommended for all iOS 9 users.
iOS 9.3.4 is likely to be the last update to iOS 9, with iOS 10 coming in September alongside new iOS devices.
iOS 10 brings a slew of new features, including a revamped Lock screen experience, an overhauled Messages app with new functionality and its own App Store, a new Photos app with object and facial recognition, a redesigned Music app, a centralized HomeKit app, and a Siri SDK for developers.
Update: iOS 9.3.4 fixes the Pangu iOS 9.3.3 jailbreak exploit. In a support document covering the security fix included in the update, Apple credits Team Pangu with discovering a vulnerability related to a memory corruption issue.