"Hey Siri" support and possibly wireless charging case alongside AirPower charging mat.
Apple Seeds Second Beta of iOS 10.3.2 to Developers
Registered developers can download the second iOS 10.3.2 beta from the Apple Developer Center or over-the-air with the proper configuration profile installed.
We don't yet know what features or improvements are coming in iOS 10.3.2 as Apple doesn't offer detailed release notes and nothing notable was discovered in the first iOS 10.3.2 update.
As a minor 10.x.x update, we can expect iOS 10.3.2 to offer bug fixes and performance improvements rather than outward-facing features. Apple has said that the update fixes SiriKit car commands, which should be working as expected.
If we find anything new in the second iOS 10.3.2 beta, we'll update this post.