Windows 10 Mobile build 10581

Windows 10 Mobile build 10581 is a build of Windows 10 Mobile. It was released to Windows Insiders in Fast Ring on 29 October 2015.

This build mostly includes small improvements and bug fixes.

Improvements and bug fixes

 * In Lumia Icon, Lumia 1520 and Lumia 930; the "Hey Cortana" feature works again.
 * The user can now select photos for sharing to third party apps such as Facebook Messenger, Facebook, Instagram Beta, WhatsApp etc.
 * Improved battery life.
 * Fixed an issue where some apps cannot be chosen for quick actions on the Lock Screen.
 * Improvements to auto-correction and text prediction.
 * Improved video recording functionality.
 * Visual Voicemail syncing now works again.
 * Dual-SIM issues that appeared in build 10572 have been fixed.
 * Fixed an issue that stopped Chinese Pinyin QWERTY working. This bug also appears in build 10572.

Bugs and quirks

 * Devices may experience a black screen for 5 minutes between spinning gears and final stages of the update. The exact time depends on the device.
 * The user is unable to set default save locations via Settings > System > Storage and it does not reflect the current storage configuration.
 * Deploying Silverlight apps from Visual Studio to the user's phone does not work in this build.
 * If the user restores a backup from another phone, the Start screen may be corrupted. The only workaround is to set a different background in Settings > Personalization > Start.

SD Card problems

 * If there is an SD card in the user's phone, it will show a garbled name in Settings > System > Storage page.
 * Moving apps to SD card may result in apps crashing. The only workaround is to reboot the phone.