Locate the user
Geolocate the user and then center the map on their current location
<!DOCTYPE html>
    <meta charset='utf-8' />
    <meta name='viewport' content='initial-scale=1,maximum-scale=1,user-scalable=no' />
    <script src='https://api.tiles.mapbox.com/mapbox-gl-js/v0.38.0/mapbox-gl.js'></script>
    <link href='https://api.tiles.mapbox.com/mapbox-gl-js/v0.38.0/mapbox-gl.css' rel='stylesheet' />
        body { margin:0; padding:0; }
        #map { position:absolute; top:0; bottom:0; width:100%; }

<div id='map'></div>
mapboxgl.accessToken = '<your access token here>';
var map = new mapboxgl.Map({
    container: 'map', // container id
    style: 'mapbox://styles/mapbox/streets-v9',
    center: [-96, 37.8], // starting position
    zoom: 3 // starting zoom

// Add geolocate control to the map.
map.addControl(new mapboxgl.GeolocateControl());

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