AltiMulti Java console. Connect to the Altimeter using the USB cable, bluetooth or 3DR telemetry module. You can do it on Windows, Linux or Mac, retrieve all the flights data and setup the altimeter.
Note that I have also done an Android version that can be run on a phone or a tablet which is quite conveniant when you are on the field.
If you want to modify the code you will need to install to install Eclipse on your computer.
When running on Windows 32 or 64 bit make sure that you install the correct usb serial library. Same goes for Mac or Linux You can run it from the jar file on all platform. For Windows I have compiled some executable.