Question: I would like to get the exact GPS location of the connected user by using the actual GPS of the phone for mobile users. Using DART.

Answer: 
You have to use [getCurrentPosition](https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/dart-dom-html.Geolocation#id_getCurrentPosition) or [watchPosition](https://api.dartlang.org/apidocs/channels/stable/dartdoc-viewer/dart-dom-html.Geolocation#id_watchPosition). Note that those methods take several optional named parameters. By default, the location is not necessarly the most accurate and you have to use `geolocation.getCurrentPosition(enableHighAccuracy: true)` to get better precision.

**But be careful** to the battery usage. Depending on the parameters you use the battery consumption will really change.
I haven't used it myself yet but I thing you can start at

```dart
dom.window.navigator.geolocation.getCurrentPosition()
    .then((e) => print(e.coords.longitude));

```