The first step in any Wi-Fi assessment is to explore your surroundings for surprises on the 2.4 and 5 GHz bands. Free WLAN discovery tools exist for nearly every OS, from the infamous Win32 NetStumbler to Meraki's Java Cloud Stumbler. Our current fave is the Android WiFi Analyzer. With this handy tool, we can record SSIDs and APs, graph real-time channel usage and signal strength, and even locate selected APs – using nothing more than the smartphone in our pocket.