How do I find my height above sea level?

[TSN79]

I'm under the impression that this takes special equipment? We're talking centimeter precision by the way. Shouldn't I be able to get this from some App by now?!

 

[davenn]

It is specialist equip! :)
Top of the line GSP systems I work with will give you 1 to 1.5 cm (10 - 15mm)accuracy at a cost of $20,000 or so because multiple units are needed for that sort of accuracy

standard handheld GSP units like the Garmin E-Trex etc will give down to maybe 3-5 metres of accuracy

Dave

Ohh I should actually qualify that ... We find that the vertical accuracy averages ~ half the quality of horizontal accuracy. So for a horizontal accuracy of 1cm, which under good conditions is quite achievable,
the vertical accuracy will be ~ 2cm

 

[Huyen401]

It is possible to achieve centimeter precision using some apps, but it does require special equipment. Some apps use GPS technology to provide location data, but the accuracy of GPS can vary and may not be precise enough for your needs. To achieve centimeter precision, you would need to use a high-precision GPS receiver or other specialized equipment. Additionally, factors such as interference and signal strength can also impact the accuracy of GPS data. So while it is possible to get centimeter precision from some apps, it may not be reliable or consistent enough for your needs. It's always best to do some research and consider your specific requirements before relying on any app for precise measurements.