Colasoft Capsa AlternativesNetwork Analyzers and other similar apps like Colasoft Capsa

Wireshark is a premier network protocol analyzer used globally in industries and education, offering multi-platform support, deep protocol inspection, powerful display filters, and VoIP analysis. It allows both live capture and offline analysis, supporting various networks and protocols.

tcpdump is a common packet analyzer that runs under the command line. It allows the user to intercept and display TCP/IP and other packets being transmitted or received over a network to which the computer is attached.

Ettercap is a suite for man in the middle attacks on LAN. It features sniffing of live connections, content filtering on the fly and many other interesting tricks.

Microsoft Network Monitor is a packet analyzer. It enables capturing, viewing, and analyzing network data and deciphering network protocols. It can be used to troubleshoot network problems and applications on the network.

NetworkMiner is a Network Forensic Analysis Tool (NFAT) for Windows. NetworkMiner can parse PCAP files and regenerate/reassemble transmitted files and certificates from PCAP files with HTTP, FTP, SMB, SMB2, TFTP and several other protocols.

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.

If you're debugging on a remote machine with a large pcap and no desire to scp it back to your desktop, termshark can help!

PlayCap plays back captures made from Wireshark, tcpdump, WinDump, or any libpcap-based application. PlayCap was originally (and still is) a part of IG Scanner by Signal 11 Software, but was spun off as a separate app and released as Open Source software.

Appknox is a mobile app security testing solution to detect and fix vulnerabilities in mobile apps using a combination of automated and manual tests.

Packet capture/Network traffic sniffer app with SSL decryption. Not that feature rich yet, but it's a powerful debugging tool especially when developing an app.

HttpCanary is a powerful HTTP/HTTPS/HTTP2/WebSocket/TCP/UDP packets capture and analyzer app designed for Android platform.

packeth is GUI and CLI packet generator tool for ethernet. Primary it is developed and maintained for Linux, but some ports for Windows and MAC have also be done. It allows you to create and send any possible packet or sequence of packets on the ethernet link.