The iPod Touch is also the first of the iPod line to be able to set up a wireless connection with the iTunes store,as well as the AppStore from where apps may be purchased and directly downloaded to the device. Apple sold over 32 million copies of the iPod Touch as of the end of 2009.
The second iPod Touch generation was presented on September 9 2008 at the "Let's Rock" keynote and featured external volume controls,a built-in speaker, Nike+ and Bluetooth support,as well as the ability to connect a microphone. The third generation of the iPod Touch runs by Apple's iOS 3.1 and was announced and released on September 9,2009 and is available in 32 GB and 64 GB models. The 8 GB second generation iPod Touch was also kept. The third generation includes faster hardware (the same microprocessors, RAM, and graphics memory as the iPhone 3GS),a slightly lower battery life than its predecessor, light sensor and bundled earphones with remote and microphone.
Both second and third generations can be updated to iOS 4.x but cannot take advantage of the features that use the iPhone's camera and GPS receiver. On September 1, 2010, Apple released the fourth generation iPod Touch that includes two cameras,one for FaceTime and one for photographs and HD video recording,a microphone for communication and voice memos,as well as Apple's A4 for faster processing. The fourth generation also includes a three-axis gyroscopic sensor that helps the iPod determine how far,fast and in which direction was it moved. The iPod Touch 4G comes with iOS 4.1 that brings Game Center to iOS as well as the possibility of using FaceTime through Wi-Fi connections.
The home screen called SpringBoard displays icons that represent all available applications.All generations of the iPod Touch have applications such as Music,Video,Photos,YouTube, Safari, Calendar, Clock,Calculator, Settings and iTunes(used for accesing the online iTunes store). Later versions included mail (access to POP/IMAP/SMTP e-mail), Maps, Stocks, Notes and Weather, which could also be purchased for earlier versions by executing a software upgrade.The iPod Touch users can directly add web pages called web clips to their home screen,as the device is equipped with Wi-Fi connectivity. On July 11,2008,the 2.0 version of Apple's OS update was available for purchase,and gave iPod Touch first generation users the possibility of accessing the AppStore and downloading third-party content to their devices.
This software update also fixed some minor bugs. On June 17,2009,Apple released the OS 3.0 update that allowed users to execute new apps,unlocked the Bluetooth function for the second generation of the device and enabled A2DP and P2P apps,as well as file transfer from an iPod Touch to another non-Apple device,such as a Bluetooth enabled mobile phone.