What specs to look for in a router to connect multiple Apple and non-Apple devices efficiently? I have a router at the moment that keeps dropping Airplay connection between different iOS devices. I'm trying to find a better router that can withstand the amount of interference from various devices such as multiple iPhones, iPads, MacBooks, Windows laptops, AppleTV, and a TV.

I know the iPad (1 and 2) and the iPhone cannot use 5 Ghz wireless signals, yet the AppleTV and retina MacBook Pro do. So I am not sure if I need to get a dual band router that can send both 2.4 Ghz and 5 Ghz, or just stick to 2.4 Ghz single band transmitter.

I would appreciate your advice for what to look for in a router to achieve what I mentioned?
It depends what you expect to get out of a router.

I just use an AirPort Extreme, and at any time there are at least 7 devices connected, 3 of which are on the 5ghz band, 3 are on 2.4ghz, and the other 2 are wired.

It's possibly the most reliable router I've had, and is incredibly easy to configure and maintain.

I also have 2 hard drives and a printer connected to it's USB port via a USB hub.

The only issue I have with it is that it doesn't play nicely if I try to set-up an incoming VPN connection on my Windows server, however it does work if I run a VPN on an OS X server I borrowed to test.