Barometric altimeter on 'future' Freerunner ?

[Stroller]

On 17 May 2008, at 22:17, Philippe Guillebert wrote:
> Matthias Schulze wrote:
>> I am wondering about applications possible with the Freerunner
>> (connected via usb) or later phone models, if a barometric altimeter
>> would be included.
>>
> Hi,
>
> Err, doesn't GPS give us a pretty accurate altitude already ?

lol.

No.

> Event if the precision is something like +/- 20 meters, I believe  
> it's got a better accuracy than a barometric altimeter that you've  
> got to calibrate to the meteorological conditions all the time.

GPS altitude precision is more like +/- 200 metres. Even cheap  
electronic altimeters are accurate to a few feet. That they need  
daily calibration makes them only of use to people who actually  
_need_ to know their height - an altimeter built into a digital  
watch, for instance, is usually no more than a gimmick, but a hang- 
glider pilot can simply hold down the "zero" button on his £100  
altimeter for 3 seconds and then knows his height accurately for the  
duration of the day's flying.

Stroller.