I wrote this very simple network tester to quickly check the TCP and UDP connectivity (expecially as for NAT) among various device while writing ViaVoip (see ViaVoip project page).
It's very trivial, yet it can be very usefull, so I thought that it was worth to publish it.
It works on Windows, Linux, Mac OS X and Android
Here very brief usage instructions:
https://sourceforge.net/p/netprobe/src/HEAD/tree/README
Screen capturing tool for Android handsets connected via USB to a desktop/laptop. It is great for fullscreen presentations, product demos, automatic screen recording, or just a single screenshot. Without root.