Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
NetStumbler - Official source of information about Netstumbler.
Debookee - Debookee is the simplest & most powerful network traffic analyzer for macOS.
SmartSniff - SmartSniff is a packet sniffer that capture TCP/IP packets and display them as sequence of conversations between clients and servers.
inSSIDer - inSSIDer Essential makes it easy to maintain small business WiFi.
Packet Peeper - Packet Peeper is a free network protocol analyzer (packet sniffer) for Mac OS X.