Here's the official changelog (with relevant items to mobile in bold):
- Addressed issue introduced by KB4022716 where Internet Explorer 11 may close unexpectedly when you visit some websites.
- Addressed issue to improve MediaCreationTool.exe support for Setup Tourniquet scenarios.
- Addressed issue with CoreMessaging.dll that may cause 32-bit apps to crash on the 64-bit version of the Windows OS.
- Addressed an issue where Visual Studio or a WPF application may terminate unexpectedly (stops responding, followed by a crash) when running on a pen and/or touch enabled machine with Windows 10 Creators Update.
- Addressed issue that causes the system to crash when certain USB devices are unplugged while the system is asleep.
- Addressed issues with screen orientation that stops working after lid close and lid open transitions.
- Addressed issue that causes .jpx and .jbig2 images to stop rendering in PDF files.
- Addressed issue where users could not elevate to Administrator through the User Account Control (UAC) dialog when using a smart card.
- Addressed issue where input using the Korean handwriting feature dropped the last character of a word or moved it to the next line incorrectly.
- Addressed issue with a race condition between the App-V Catalog Manager and the Profile Roaming Service. A new registry key is available to control the waiting period for App-V Catalog Manager, which allows any third-party Profile Roaming Service to complete.
- Security updates to Internet Explorer 11, Microsoft Edge, Windows Search, Windows kernel, Windows shell, Microsoft Scripting Engine, Windows Virtualization, Datacenter Networking, Windows Server, Windows Storage and File Systems, Microsoft Graphics Component, Windows kernel-mode drivers, ASP.NET, Microsoft PowerShell, and the .NET Framework.
In today's malware-strewn and fraudulent times, we should never disregard security fixes though, so update today in all affected mobiles, just in case!