Bubble Level: surprisingly useful

You can get the same functionality, including calibration, by downloading the Labyrinth game from AppStore. Not only is it a fun game, but the settings option has a two dimensional "bubble" level device.

So you can use it flat on its back, but can you use it resting the iPhone on its left or right side (to level a painting)?

Hey great...but can it make phone calls. Sheesh!

RE: Three dimensions vs. two: I was obviously mistaken. The interface makes it look like the bubble travels in three dimensions, up a curved glass hemisphere.

I have corrected the article, and appreciate your attention to detail.

I like this -- someone should write a program that turns the iPhone into a hammer! :-)

"Bonus: it tracks how level the device is in three dimensions: laying your iPod or iPhone on a table allows the bubble to travel toward the center circle on the interface."

Please explain to me how you would use this in three dimensions. Does it also display you high the device is off the ground?

The rouded back of the 3G is flat enough to use the iPhone as a good level. So this will work on a first gen iPhone, iPod touch and 3G.

The iPhone developer example app had a nicer calibration routine. You put it down, clicked a button, then flipped it over and it figured out the difference. That accelerometer is going to drift, and it'll be a pain to grab a real level every time you want to calibrate it.

Or you could have installed the free version of labyrinth and used that as a 2 way level.....

Check out "Labyrinth Lite", the free little game where you move a marble through a maze. In the settings, there is a very nice bubble level! -Mike, author of EmailContact for iPhone