Android KitKat

Android KitKat

Version of the Android operating system
Android 4.4.2 KitKat running on a Nexus 5
Developer	Google
Released to manufacturing	October 31, 2013; 10 years ago (2013-10-31)
Final release	4.4.4_r2.0.1 (KTU84Q)[1] / July 7, 2014; 10 years ago (2014-07-07)
Kernel type	Monolithic (Linux)
Preceded by	Android 4.3.1 "Jelly Bean"
Succeeded by	Android 5.0 "Lollipop"
Official website	www.android.com/versions/kit-kat-4-4/
Support status
Unsupported since 2017, Google Play Services support dropped since August 2023

Android KitKat is the codename for the eleventh Android mobile operating system, representing release version 4.4. Unveiled on September 3, 2013, KitKat focused primarily on optimizing the operating system for improved performance on entry-level devices with limited resources.

The first phone with Android KitKat was the Nexus 5.

As of October 2022,^[update] 1.39% of Android devices run KitKat.^[2] On July 24, 2023, Google announced that Google Play Services would no longer support KitKat in August of that year.^[3][4][5]

History

Android 4.4 "KitKat" was officially announced on September 3, 2013. The release was internally codenamed "Key lime pie"; but John Lagerling, director of Android global partnerships, and his team, decided to drop the name, arguing that "very few people actually know the taste of a key lime pie". Aiming for a codename that was "fun and unexpected", his team pursued the possibility of naming the release "KitKat" instead. Lagerling phoned a representative of Nestlé, who owns the Kit Kat brand and produces the confectionery (outside the United States, where it is produced by The Hershey Company under license), and quickly reached a preliminary deal for a promotional collaboration between the two companies, later finalized in a meeting at Mobile World Congress in February 2013. The partnership was not revealed publicly, or even to other Google employees and Android developers (who otherwise continued to internally refer to the OS as "KLP"), until its official announcement in September.^[6][7]

As part of the promotional efforts, Kit Kat bars in the shape of the Android robot logo were produced, while Hershey ran a contest in the United States with prizes of Nexus 7 tablets and Google Play Store credit.^[7][8]

The Nexus 5, developed by LG Electronics, was unveiled on September 30, 2013, as the launch device for KitKat.^[9]

Up to October 2017, Android 4.4 was still supported with security patches by Google for the source code.^[10][11][12]

Development

Continuing on from the focus on improving visual performance and responsiveness on Android 4.1 "Jelly Bean", the main objective of Android 4.4 was to optimize the platform for better performance on low-end devices, without compromising its overall capabilities and functionality. The initiative was codenamed "Project Svelte", which Android head of engineering Dave Burke joked was a weight loss plan after Jelly Bean's "Project Butter" added "weight" to the OS.^[13] To simulate lower-spec devices, Android developers used Nexus 4 devices underclocked to run at a reduced CPU speed with only a single core active, 512 MB memory, and at 960×540 display resolution—specifications meant to represent a common low-end Android device.^[13]

A development tool known as ProcStats was developed in order to analyze the memory usage of apps over time, especially those that run background services. This data was used to optimize and decouple Google apps and services found to be inefficient, thus helping to reduce the overall memory usage of Android. Additionally, 4.4 was designed to be more aggressive in managing memory, helping to guard against apps wasting too much memory.^[13][14]

Features

See also: Android version history § Android 4.4 KitKat

User experience

The overall interface of KitKat further downplays the "Holo" interface appearance introduced on 4.0, replacing remaining instances of blue accenting with greys and white (such as the status bar icons), and getting rid of the Wi-Fi upstream and downstream traffic indicators (triangles pointing up and down), though they can still be seen in the quick control center menu.^[15]

The Wi-Fi icon colour when only a connection to an access point with no Internet access has been established has changed from grey to orange.^[16]

The appearance may deviate in custom vendor distributions such as TouchWiz.

Apps may trigger a translucent status and navigation bar appearance, or trigger a full screen mode ("Immersive mode") to hide them entirely. The launcher also received a refreshed appearance, with the implementation of the translucent navigation bars, and the replacement of the black backdrop in the application drawer with a translucent backdrop.^[17][18] Additionally, action overflow menu buttons in apps are always visible, even on devices with the deprecated "Menu" navigation key.^[19] In the Settings menu, users can now specify a default Home (launcher) and text messaging app.^[20]

On stock devices, the Messaging and Movie Studio apps were removed; the former was replaced by Google Hangouts, which supported SMS. The AOSP Gallery app was also deprecated in favor of Google+ Photos.^[17]

Platform

A new runtime environment known as the Android Runtime (ART), intended to replace the Dalvik virtual machine, was introduced as a technology preview in KitKat.^[21] ART is a cross-platform runtime which supports the x86, ARM, and MIPS architectures in both 32-bit and 64-bit environments. Unlike Dalvik, which uses just-in-time compilation (JIT), ART compiles apps upon installation, which are then run exclusively from the compiled version from then on. This technique removes the processing overhead associated with the JIT process, improving system performance.^[22]

Devices with 512 MB of RAM or less report as "low RAM" devices. Using an API, apps may detect low RAM devices and modify their functionality accordingly. KitKat also supports zram.^[14][18] WebView components were updated to utilize a version of the Google Chrome rendering engine.^[23] A new Storage Access Framework API allows apps to retrieve files in a consistent manner; as part of the framework, a new system file picker (branded as "Documents") allows users to access files from various sources (including those exposed by apps, such as online storage services).^[24]

A public API was introduced for creating and managing text messaging clients.^[25] Sensor batching, step detection and counter APIs were also added.^[18] KitKat supports host card emulation for near-field communications, which allows apps to emulate a smart card for activities such as mobile payments.^[26]

See also

• Android version history
• iOS 7
• Windows Phone 8
• Windows 8
• OS X Mavericks

References

1. "Android Source". Google Git. Archived from the original on June 13, 2021. Retrieved May 28, 2021.
2. "Mobile & Tablet Android Version Market Share Worldwide". StatCounter Global Stats. Archived from the original on July 14, 2020. Retrieved November 16, 2020.
3. "Google Play services discontinuing updates for KitKat (API levels 19 & 20) starting August 2023". Android Developers Blog. Archived from the original on July 25, 2023. Retrieved July 25, 2023.
4. Li, Abner (July 24, 2023). "Google Play services ending support for Android 4.4 KitKat". 9to5Google. Archived from the original on July 24, 2023. Retrieved July 25, 2023.
5. Amadeo, Ron (July 25, 2023). "Android 4.4 KitKat is truly dead, loses Play Services support". Ars Technica. Archived from the original on July 26, 2023. Retrieved July 26, 2023.
6. "Android 4.4 KitKat: What's the point of co-branding?". CNET. Archived from the original on December 23, 2015. Retrieved November 2, 2015.
7. Kelion, Leo (September 3, 2013). "Android KitKat announced". BBC News. Archived from the original on September 4, 2013. Retrieved September 3, 2013.
8. "Kit Kat contest up and running, win one of a 1000 Google Nexus 7 (2013) slates being given away". PhoneArena. Archived from the original on March 4, 2016. Retrieved November 2, 2015.
9. "Google Unveils Nexus 5 With Android 4.4 KitKat". PC Magazine. Archived from the original on March 4, 2016. Retrieved December 29, 2015.
10. "Android Security Bulletin—October 2017 | Android Open Source Project". Android Open Source Project. Archived from the original on July 5, 2018. Retrieved July 2, 2018.
11. "Security updates and resources". Android.com. Android Open Source Project. Archived from the original on January 12, 2017. Retrieved September 10, 2017. When a security vulnerability in AOSP is fixed in an Android Security Bulletin, we'll notify Android partners of issue details and provide patches. The Android security team currently provides patches for Android versions 4.4 (KitKat) and above. This list of backport-supported versions changes with each new Android release.
12. "Android Security Bulletin – April 2017". Android.com. Android Open Source Project. Archived from the original on April 19, 2017. Retrieved April 5, 2017.
13. "How Google Shrank Android For Version 4.4 KitKat". ReadWrite. Archived from the original on October 19, 2015. Retrieved November 2, 2015.
14. "Android 4.4 KitKat to run "comfortably" on 512MB RAM devices, here's how". PhoneArena. Archived from the original on January 29, 2017. Retrieved November 2, 2015.
15. Amadeo, Ron (November 14, 2013). "Android 4.4 KitKat, thoroughly reviewed". Ars Technica. Archived from the original on October 24, 2020. Retrieved October 24, 2020.
16. "Android 4.4 KitKat: Warum die Statussymbole weiß und statisch sind". GIGA (in German). November 19, 2013. Archived from the original on October 24, 2020. Retrieved October 24, 2020.
17. Amadeo, Ron (June 16, 2014). "The history of Android: The endless iterations of Google's mobile OS". Ars Technica. Archived from the original on July 5, 2014. Retrieved July 6, 2014.
18. Molen, Brad (November 5, 2013). "Nexus 5 review". Engadget. Archived from the original on November 9, 2013. Retrieved November 11, 2013.
19. "Android menu button now on by default on all device with KitKat". PhoneArena. December 9, 2013. Archived from the original on December 13, 2013. Retrieved February 9, 2014.
20. "How to remove Hangouts and more Android 4.4 KitKat apps". CNET. Archived from the original on November 9, 2015. Retrieved November 2, 2015.
21. "'ART' experiment in Android KitKat improves battery life and speeds up apps". Engadget. Archived from the original on January 27, 2017. Retrieved June 26, 2014.
22. Andrei Frumusanu (July 1, 2014). "A Closer Look at Android RunTime (ART) in Android L". AnandTech. Archived from the original on July 5, 2014. Retrieved July 5, 2014.
23. "KitKat's WebView is powered by Chromium, enabling Android app developers to use new HTML5 and CSS features". The Next Web. November 2, 2013. Archived from the original on October 6, 2015. Retrieved November 2, 2015.
24. Ho, Joshua. "Examining MicroSD changes in Android 4.4". Anandtech. Archived from the original on March 28, 2014. Retrieved March 28, 2014.
25. "Getting Your SMS Apps Ready for KitKat". Android Developers Blog. Archived from the original on October 15, 2013. Retrieved October 14, 2013.
26. "Google gets around the carriers with Host Card Emulation for NFC payments". NFCWorld.com. October 31, 2013. Archived from the original on October 2, 2015. Retrieved November 2, 2015.

External links

• Media related to Android KitKat at Wikimedia Commons
• Official website