So I have an older Airport Extreme, that cannot do 2.4 and 5 GHz simultaneously. I was noticing a lot of issues with interference, so I switched it to 5 GHz only. It now works great for my computers and iPad, but obviously doesn't work on the iPhone. I was thinking about buying the newer Airport Extreme, but then I thought of a cheaper option: could I connect an Airport Express to the network as a bridge, and run that on the 2.4GHz? Ideally, I'd like to create a separate network SSID that I used just to connect my phones (or for visitors with older computers). Could I do that wirelessly, or would I have to plug the Express into the Extreme? Networking isn't my speciality, so thanks in advance for pointing me in the right direction.