Though a simulator is fully available for multiple Android platforms, it can get cumbersome to test on it every little change a programmer does in his/her program. The fastest way to test your programs is still loading it on an actual device. Not bragging here, but we look forward to testing our applications on one of the best devices for such a task: the Nexus One.
Besides the capacitive multi-touch screen, on a Nexus One various types of inputs are accessible: GPS receiver, 3-axis Accelerometer, Magnetic Compass, Proximity / Light sensor and even noise cancelling dual microphones, managed by a voice processor developed by Audience. [1] [2]
A developer can use Nexus One to test applications in two ways:
[1] http://en.wikipedia.org/wiki/Nexus_One
[2] http://www.thesearethedroids.com/2009/12/14/nexus-one-hardware-running-list/