NetworkingTest is a UDP client and server. It lets you send messages (either to a particular IP or broadcasted) and receive them. It logs the received messages and timestamps them down to the millisecond. Since it is written in Qt, you will be prompted to install Ministro during NetworkingTest's first run. Once Ministro is installed, it will download the Qt libraries.
ChrisK is the official developer of the app which can be found in the Tools category. Over 100 users installed NetworkingTest and the most recent update was released on Feb 19, 2013. Google Play displays that this application is rated 4.5 by its users.