"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
AirPods and AirPower: Everything We Know
Apple Seeds Second Beta of iOS 10.3.2 to Public Beta Testers
Beta testers who have signed up for Apple’s beta testing program will receive the iOS 10.3.2 beta update over-the-air after installing the proper certificate on their iOS device.
Those who want to be a part of Apple’s beta testing program can sign up to participate through the beta testing website, which gives users access to both iOS and macOS Sierra betas. Betas are not stable and include many bugs, so they should be installed on a secondary device.
According to Apple’s release notes, the iOS 10.3.2 update fixes SiriKit car commands, which should now be working as expected. Aside from the SiriKit fix, we don’t know what other bug fixes and improvements are included, as nothing notable has been discovered in the betas we’ve received so far.
As a minor 10.x.x update, iOS 10.3.2 likely focuses on bug fixes, performance improvements, and security enhancements rather than outward-facing features.