It is a small piece of networking hardware that sends received media data such as video and audio to a TV or external display.

It is based on a Pentium M processor and ran a variant of Mac OS X Tiger, and included a 40 GB hard disk for storing content.

[12] At launch, Apple TV required a Mac or Windows-based PC running iTunes on the same network to sync or stream content to it.

Due to its thermal management design utilizing the upper case as a passive heat sink, the device gets warm when in use.

The device has 8 GB of flash storage for buffering, replacing the internal hard drive in the first-generation model.

The remote replaced the arrow button with swipe-to-select features, Siri support, a built-in microphone, volume control over HDMI CEC and IR, and an accelerometer (IMU).

Several unexpected problems, such as incompatibility with iTunes Remote app for iOS and watchOS,[42] were fixed by Apple in tvOS 9.1 on December 8, 2015.

[43] On September 13, 2016, Apple released tvOS 10, bringing an updated remote app, single-sign on, and light-on-dark color scheme.

Its HDMI port supports ARC and eARC, which allows other sources plugged into the television to output audio through Apple TV, including to AirPlay speakers like HomePod.

It can pair with the ambient light sensor on iPhones with Face ID to optimize its color output, a feature that was also extended to older Apple TVs with tvOS 14.5.

[51] AirPlay supports high frame rate HDR playback, allowing videos shot on the iPhone 12 Pro in Dolby Vision 4K 60fps to be mirrored in full resolution.

Pairing a Wireless keyboard with the tvOS on the Apple TV enables another accessibility feature that also is an incorporation of VoiceOver.

[76] Similar to Google's redesign of YouTube, Apple has restricted access to most viewed charts on movies and podcasts.

[78] Apple TV allows users on a computer running iTunes to sync or stream photos, music and videos.

[79] A user can connect a computer on a local network to maintain a central home media library of digitized CD, DVD or HD content,[80] provide direct connectivity to photo organization software such as iPhoto,[81] limit home video access to a local network only,[82] play Internet radio,[83][84] or preload content on Apple TV to be used later as a non-networked video player.

Apple TV HD and newer can also stream content locally using third-party apps such as Plex, Kodi, VLC media player, Emby and MrMC.

[98] There is an Apple TV export option in QuickTime which allows content in some formats that the device does not support to be easily re-encoded.

The first-generation Apple TV had component video and RCA connector audio ports, both removed in the 2nd generation.

[citation needed] AirPlay allows iOS devices or an AirPort-enabled computer with the iTunes music player to send a stream of music to multiple (three to six, in typical conditions) stereos connected to an AirPort Express (the audio-only antecedent of Apple TV) or Apple TV.

[106] The AirPort Express' streaming media capabilities use Apple's Remote Audio Output Protocol (RAOP), a proprietary variant of RTSP/RTP.

[121] It is a completely redesigned remote that features dual microphones for Siri support and a glass touch surface for navigation around the interface by swiping or tapping and scrubbing to fast forward or rewind.

The Siri Remote communicates with the Apple TV via Bluetooth rather than infrared, removing the requirement of a line-of-sight with the device.

This update did away with Front Row and introduced a new interface in which content was organized into six categories, all of which appeared in a large square box on the screen upon startup (movies, TV shows, music, YouTube, podcasts, and photos) and presented in the initial menu, along with a "Settings" option for configuration, including software updates.

[131] The 2nd[132] and 3rd[133] generation Apple TVs run a version of iOS, rather than the modified Mac OS X of the original model.

The interface on Apple TV Software 4 is similar to that of previous versions, with only minor changes and feature additions throughout.

[142] A new development feature, App Thinning,[143] is used in the Apple TV, running on tvOS, due to the storage restrictions of the device (as little as 32 GB) and the dual-use of the NAND Flash Memory to precache movies from Apple's content servers as well as storage for downloaded applications from the tvOS App Store.

Developers have reacted with criticism toward the download size limits, arguing that it leads to situations where game data is purged and has to be re-downloaded.

Although this is a higher frequency and the difference is not audible, it is seen by some as falling short of digital transmission of data standards due to the audio not being 'bit perfect'.

[190] Due to the growth of digital TV and consumers turning to Internet media services, an analyst at the time predicted sales of 6.6 million Apple TVs by the end of 2009.

Tim Cook announced at the All Things Digital conference in May 2012 that Apple had sold 2.7 million of the 3rd generation model in 2012.