Sonos audio systems have really taken off in recent years thanks to a simple but crucial addition: free iOS apps that turn any iPhone, iPod Touch, or iPad into a Sonos touch-screen remote. (The iPhone and iPad apps will soon be joined by one for Android phones.) But thanks to Apple's heavy-handed App Store restrictions, the Sonos app can only control the Sonos components accessing Internet- or PC-based music; you can't stream any music from your iPod, iPhone, or iPad to the Sonos devices.
Thankfully, Sonos has created a workaround: the Sonos WD100 Wireless Dock for iPod and iPhone. The accessory turns your iPod or iPhone into a pseudonetworked drive, allowing you to play all the iTunes music housed on your Apple device in any room where you have a Sonos ZonePlayer system set up.
To be clear, Sonos ZonePlayers (the ZP90, ZP120, or S5) can already stream music files from iTunes libraries on networked PCs and Macs throughout the house. And they also work with some music libraries on some NAS (network-attached storage) drives. But using the iPod dock allows you to accomplish the same thing without leaving a power-hungry PC turned on, and without navigating the often convoluted world of NAS drive setup and management. It's a lot easier for the average person (read: non-techie) to just drop an iPod or iPhone into the dock. That's exactly what makes the WD100 Wireless Dock appealing.
The first thing you have to do is plug the dock in and add it to your Sonos system just as you would a ZonePlayer--that's accomplished via the Sonos desktop software (Mac or Windows) or the iPhone or iPad app. You then dock your iPod or iPhone (yes, your device's battery will recharge while it's in the dock) and select Browse to access your collection of music on the device. (The only minor tricky part in the setup was figuring out that you had to hit the browse button to call up your music library.) Once you discover your music, you're good to start selecting tracks to play just as you would from the music library on your computer.