Windows Phone 8.1

History

Windows Phone 8.1 was initially rumored under the codename Windows Phone Blue, a series of updates coinciding with Windows 8.1. Microsoft originally planned to release it in late 2013, shortly after the PC counterpart, but general distribution was pushed back to early 2014. Instead of waiting over a year for new features, Microsoft released three incremental updates to Windows Phone 8: GDR2 (Lumia Amber) introduced Data Sense; GDR3 (Lumia Black) added support for quad-core processors, 1080p screens up to six inches, a Driving Mode, and extra live tile rows for larger phablets.

The final name leaked when the Windows Phone 8.1 SDK was released to developers on February 10, 2014. Official announcement came at Microsoft's Build conference keynote on April 2, 2014, alongside the Windows 8.1 Update. The final shipping code was released to registered users of the Preview for Developers program on April 14, 2014, and to the general public in subsequent months, with release dates determined by wireless carriers and accompanied by firmware updates including Lumia Cyan.

These updates were complete, finished versions of the OS, unlike the preview builds in the Windows Insider program for Windows 10 Mobile.

Features

Windows Phone 8.1 introduced Cortana, a personal virtual assistant similar to Google Now and Apple's Siri, named after the Halo video game series. Cortana can set reminders, recognize natural voice without predefined commands, and answer questions using Bing information such as weather, traffic, sports scores, and biographies. It includes a Notebook feature that automatically gathers user information and interests based on usage, allows input of personal details like quiet hours and close friends who can bypass them, and lets users delete undesirable information.

Universal Bing SmartSearch features from Windows 8.1 are incorporated into Cortana, replacing the previous Bing Search app activated by the Search button. Cortana was released in beta in the United States in the first half of 2014 and in China, the United Kingdom, India, Canada, and Australia in August 2014. Microsoft committed to updating Cortana twice a month with new features including more easter egg replies, UI improvements, and better voice modulations.

The default web browser is Internet Explorer 11, which includes support for WebGL, normal mapping, InPrivate mode, Reading mode, swipe navigation, a new HTML video player with inline playback and closed captions, Windows 8-style website live tiles, password saving, and unlimited tabs. Tabs sync automatically between Windows 8.1 devices and Windows Phone when logged in with the same Microsoft account.

Hardware

Windows Phone 8.1 devices were manufactured by Microsoft Mobile (formerly Nokia) and hardware partners including HTC, Gionee, JSR, Karbonn, Micromax, Samsung, Alcatel, Lava (under Lava and Xolo brands), Cherry Mobile, and Blu. Additional partners Gionee, JSR, LG, Lenovo, Longcheer, and ZTE registered to release products; Sony stated intention but did not produce devices. At Build 2014, Microsoft added Micromax and Prestigio as partners. Hardware requirements were loosened to allow adapting existing Android devices, such as the HTC One M8, to run Windows Phone, including support for virtual navigation keys that can be hidden by swiping.