Audio Playback
--Frequency response: 20Hz to 20,000Hz

--Audio formats supported: AAC (16 to 320 Kbps), Protected AAC (from iTunes Store), MP3 (16 to 320 Kbps), MP3 VBR, Audible (formats 2, 3, and 4), Apple Lossless, AIFF, and WAV

--User-configurable maximum volume limit

TV and Video
--Support for 1024 x 768 with Dock Connector to VGA adapter; 576p and 480p with Apple Composite A/V Cable, 576i and 480i with Apple Composite A/V Cable

--H.264 video up to 720p, 30 frames per second, Main Profile level 3.1 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats; MPEG-4 video, up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats

Mail attachment support
--Viewable document types: .jpg, .tiff, .gif (images); .doc and .docx (Microsoft Word); .htm and .html (web pages); .key (Keynote); .numbers (Numbers); .pages (Pages); .pdf (Preview and Adobe Acrobat); .ppt and .pptx (Microsoft PowerPoint); .txt (text); .rtf (rich text format); .vcf (contact information); .xls and .xlsx (Microsoft Excel)

Languages
--Language support for English, French, German, Japanese, Dutch, Italian, Spanish, Simplified Chinese, Russian

--Keyboard support for English (US) English (UK), French (France, Canada), German, Japanese (QWERTY), Dutch, Flemish, Spanish, Italian, Simplified Chinese (Handwriting and Pinyin), Russian

--Dictionary support for English (US), English (UK), French, French (Canadian), French (Swiss), German, Japanese, Dutch, Flemish, Spanish, Italian, Simplified Chinese (Handwriting, Pinyin), Russian

Source: Apple