You don't have to install anything to use Done-it's software. The software is a web application, which is always up-to-date. So you can use the software anywhere, anytime, as long as you have an Internet connection.
The software is also very user-friendly. When you first start using it, you can use an electronic assistant that explains to you step by step how to enter data and how to use Done-it. You can always turn the assistant on or off.