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.

tcpdump - tcpdump is a common packet analyzer that runs under the command line.

Debookee - Debookee is the simplest & most powerful network traffic analyzer for macOS.

PCAPdroid - PCAPdroid is an android app to capture the phone traffic and analyze it remotely (e.g. via Wireshark). The traffic can be easily downloaded from a remote device thanks to the integrated HTTP server, or streamed to a remote UDP receiver.

Packetyzer - Packetyzer provides a Windows user interface for the Ethereal packet capture and dissection library.

Mojo Packets - Wireless Troubleshooting Made Easy