Reminder, the team testing the new Arduino debugging tool has grown to 400+ users. If you would like to join the team and receive a free license for this tool then sign up for the forum on http://www.visualmicro.com and include a request to join the debugger beta team.
The free Visual Studio plugin is the only 100% compatible plugin for Arduino. After installing Microsoft Visual Studio Professional you will have compiled your first Arduino sketch in under 10 minutes.
Compiles any Arduino sketch at the click of a button. Allows you to see what your Arduino is doing and why, discover what hardware is connected to your Arduino using I2c, Digital and Analog graphical displays. Includes hundreds of other features such as Arduino memory free memory and runtime memory usage reporting.
Includes support for Teensy and other non-arduino cores.
Visual Studio Professional can be obtained free for over 3 years. Read more here