The best mobile WiFi scanner and wardriving tool comes to the iPhone. WiFiFoFum scans for 802.11 wireless (WiFi) networks and displays information about each network it detects; including: SSID, MAC, RSSI (signal strength), channel, AP mode, security mode and available transmission rates. WiFiFoFum also allows you to connect to networks you find.
WiFiFoFum also supports wardriving by creating logs of access point locations as they are discovered. These KML logs can then be viewed directly on the iPhone's map application or emailed so that you may view them on your desktop or laptop. To view emailed logs just paste the link in the email into the Google Maps site.
WiFiFoFum's radar view provides a graphical representation of nearby WiFi access points.

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