Aircheck G2

If you're even thinking of spending this much on a wifi tester, you're either a pro, or (like me) just mighty pissed off at some wifi coverage/interference/performance issues you can't quite solve no matter what you try. There are those phone apps that give you a channel view, they call themselves "wifi analyzers" but they really don't tell the whole story -- they just show the signal strength & channel usage of access points in view. They don't show actual traffic utilization, sources of interference, or background noise. This tool not only shows all that, it's got a super clean, usable touchscreen interface that shows at a glance exactly what's going on, organized by channel, by access point, or by network. Spend five minutes with it and you'll get a bunch of insights that would have taken you hours with other techniques, or maybe never been clear. After playing around with just a little while I had several immediately actionable observations for my setup (in terms of channel/band usage, placement, etc).