Tunlookup is a desktop app intended for translating text without much effort. The tool is quite unobtrusive as it can be configured to run from the Menu Bar and respond to keyboard shortcuts independently of the application you are running at the moment.
In terms of interface layout, Tunlookup is not very different from other translation tools. It has two main panes: one for each language in the pair. Luckily, it supports combinations of multiple source and target languages as well.
The app needs an Internet connection to perform translation jobs. Regrettably, you cannot pick your favourite Internet machine translation engine, should you wish to use one different from the default. Luckily, however, it is possible to save specific translation results to gradually build your personal glossary, which will still be available even in offline mode.
All in all, Tunlookup is a much more convenient and expedite way to carry out translations than using a web browser. Fortunately, this product can be downloaded and used without any cost.