If you’ve ever tried to send audio from your Mac to other rooms in your house, you’ve probably run into a challenge—unless you’ve set up Apple TVs or AirPort Expresses everywhere, it’s tough, and even with those devices, you’re limited to streaming from iTunes. That’s unless you’re running Rogue Amoeba’s Airfoil ($25), which was just updated to version 4.5: this app is the perfect way to send audio to all of the Macs (or PCs) on your network, and not just from iTunes. It streams from any audio source on your machine, a trick that you can’t easily pull off otherwise.
Rogue Amoeba’s solution is actually composed of two computer apps—Airfoil and Airfoil Speakers—plus Airfoil Speakers Touch for iOS devices. Install the speaker apps on whatever computers and devices you’d like, and they instantly become remote speakers. AirPorts, Apple TVs, and AirPlay devices automatically join too. They appear within a list in the Airfoil controller on your main machine—you can then toggle them on and off from there. The newest version allows you to send audio from iOS devices to your computers, and receive audio on iOS devices from computers running iTunes. You can also control tracks on apps such as Spotify, Rdio, and Radium right from the Speaker app.