Xpediter - Xpediter is a mainframe application interactive debugging tool. It also offers code coverage for mainframe application analysis.
PVS-Studio - PVS-Studio is a useful piece of software for detecting problems in source code. The software examines program codes written in C, C++, and C# for any problems that might prohibit the code from functioning properly.
Fiddler - Fiddler is a debugging program for websites.
Tenon - Tenon is an accessibility testing tool in that it is aimed at offering flexibility in tooling for designers, developers, and testers.