iTunes  Definitions and Device Types

 
Let's start with some definitions.  Key terms will be introduced, and these will be used in the following sections to explain the different ways of streaming your media to your devices.
 

iTunes

iTunes should, by now, need to no introduction.  However, in this context, we will use iTunes to mean a running installation of the iTunes application.  The iTunes library is the local media library of that running instance.
 

Home Sharing

Home Sharing is the ability for the media within an iTunes library to be accessed remotely by another iTunes instance or via an iOS device.  See the topic on configuring iTunes for iHomeServer for instructions on how to turn Home Sharing on.  Home Sharing is fundamental to allowing your devices to see your server's media therefore it is assumed that you have already configured it correctly.  Note that the Apple User ID and password you have used to configure Home Sharing on your server must match the Apple User ID and Password you have configured in the other iOS devices (or other iTunes instances) in order for Home Sharing to work successfully.
 

AirPlay

AirPlay is the ability for an iTunes instance, or an iOS device, to send its audio or video stream to another AirPlay capable device.  The device must be AirPlay capable.  Apple TVs, Apple Airport Express/Extreme and third-party audio/video devices that are certified as AirPlay compatible, are all AirPlay capable devices.  AirPlay allows you to play a song that is local to your iPhone and redirect the audio stream to your hifi.  All you need is a hifi that is AirPlay compatible, or alternatively an (inexpensive) AirPort Express adaptor plugged into it and configured to be a member of your existing wifi or wired network.  iTunes itself can also redirect its audio or video stream to an AirPlay compatible device.  An Apple TV is such a device, and this means that if you are sitting in front of your iTunes application, you can select a movie and then tell iTunes to play the movie on your Apple TV instead of on your monitor.  iTunes will then wake your Apple TV up and start playing the movie on it wirelessly.  iTunes, when playing audio tracks, can even redirect its audio to multiple AirPlay devices.  This means you can have multiple speakers configured (each with its own AirPlay receiver, such as an AirPort Express) and send your audio tracks to multiple speakers simultaneously.  Each speaker's volume can be controlled separately and AirPlay is smart enough to synchronise the audio stream so there isn't any annoying echo-ing effects.  It is a true "party-mode".
 

Remote Control App:

"Remote App" on the Apple App Store

"rtRemote App" on the Windows 8 Store

The Apple Remote App for iOS, or the rtRemote App for Windows 8, is the last piece of the puzzle.  These apps allow you to remote control an iTunes installation.  The functionality provided by both remote controls includes navigating the iTunes installation's library, selecting media, and playing that media.  However, the most useful aspect of the app is that it allows you to select which AirPlay device(s) (if any) you want the iTunes instance to send its media too.  Remote Apps coupled with AirPlay are what makes iTunes and iHomeServer together one of the best, most integrated, media platforms today.  The iTunes instance that is running under iHomeServer control can be remote controlled via the Remote App on any iPhone, iPad or iPod touch.  With just a few taps of the finger, you can select music from your server and tell iTunes to play it on any speaker system in your house.  With iHomeServer running iTunes, you can rely on iTunes to be up and available as it is running as a server; there isn't the concern that somebody has accidentally closed iTunes on your desktop thus spoiling the end-to-end integration experience by requiring you to log on to your desktop first and start iTunes up manually.
 

Capabilities by device

The table below shows which types of device support which technologies:
 
Device
Home Sharing
AirPlay
Remote App
An iTunes installation
Can act as a Home Share server (i.e. its media library can be accessed by other clients) and as a Home Share client (it can access other Home Share libraries)
 
Can AirPlay to multiple audio devices simultaneously; can AirPlay to a single video device simultaneously
The Remote App can control a running iTunes  application
iOS Device (iPad, iPhone iPod Touch)
Can act as a Home Share client only (i.e. can access the media library of an iTunes installation)
 
Can AirPlay either audio or video to a single AirPlay device simultaneously
Can be used to run the Remote App
Apple TV
Can act as a Home Share client only (i.e. can access the media library of an iTunes installation)
Can receive an AirPlay stream, either audio or video
Can be used to remote control the Apple TV - you can directly control the ATV's menus, or alternatively navigate the Apple TV's media library (or any library that the Apple TV is Home Sharing with) and play any chosen media track
 
Airport Express or Airport Extreme
 
-
Can receive an AirPlay audio stream
-
Third Party AirPlay device, eg an AirPlay speaker system
 
-
Can receive an AirPlay audio stream
-
 
 
The next section combines the terms described above into two main scenarios - pushing media from iTunes to other devices, or using other devices to pull media from an iTunes library.