Officially, Windows 10 Mobile Insider Preview Build 10586.71 contains nothing but bug fixes, including performance and reliability improvements, upgrades to the Edge browser, and power improvements as well, said Gabe Aul, corporate vice president of Microsoft’s Engineering Systems Team, in a blog post. Microsoft rolled out a similar rollup update on July 29.
Aul said, however, that the most recent releases have been performed with a broader rollout of Windows 10 Mobile in mind. Microsoft has deployed Windows 10 Mobile to the Lumia 950 and Lumia 950XL, but the vast majority of Windows phones are running Windows Phone 8.1.
It stands to reason, then, that the bug fixes the rollup release fixes are all concerned with the upgrade from Windows Phone 8.1. They include fixes to ensure that WinPhone 8.1 data profiles and messaging settings migrate during the upgrade, as well as ensuring that SensorCore motion sensor APIs, and SD cards, are properly detected. The upgrade also adds PDF support to the Edge browser, various power management improvements, and a fix to re-connect the phone to Bluetooth devices that have previously been paired.
Why this matters: Microsoft is overdue to migrate all of its existing Windows Phone 8.1 phones to the Windows 10 Mobile platform—but has to ensure that all of the different hardware configurations and carriers are supported. Microsoft’s Lumia lineup already has suffered significant losses in terms of units and revenue, so ensuring that the remaining users are able to transition smoothly to Windows 10 is critical.