Waterspeed uses the internal GPS of your device to track Speed, Heading, save the track, and calculate statistics. On the Apple Watch 2 or higher uses the internal GPS (if iPhone is not connected). Waterspeed applies filters to the GPS data received from the system, in order to avoid mistakes and adapt that to the Watersports behavior.

Please, be sure to allow access to the GPS (Location) in System Settings->Privacy->Location->Waterspeed of your iPhone and your Apple Watch. It is also important to set "Precise Location".

TIP: always use the Apple Watch, if you have any, or try to keep your iPhone not close to your body, to avoid GPS issues.

NOTE: if you experience some big mistake in your track, using the Apple Watch alone, please try to put it in Flight mode, to avoid any connection, that can be the reason for the wrong position registered.

NOTE 2: In case of mistakes or if you forget to stop the GPS when you are back to the land, use the CUT Tool or the REMOVE SPIKES tool available inside the Activity page (see the related article) or the Web App.

Waterspeed can also work with an external GPS that is natively integrated with your device and compatible with iOS 10 or higher (for example to use an iPad that doesn't have the internal GPS).

Before start tracking your session, be sure to wait until there is a GPS signal. If not, open iOS Maps, then open Waterspeed and let it search for a few minutes to lock onto a GPS signal.

Be aware that just because some maps app like Google Maps, Apple Maps, etc. may show your location on the map, this does not mean that the device's GPS is functioning properly or that a GPS fix has been obtained. The data used to show your location on the map may be based on the cellular network, Wi-Fi signals, or very poor accuracy.

Please note: continued use of GPS running in the background can dramatically decrease your battery life.