You can ask user to give you the locations, user can share from messenger location button, and select location on map or their current location.
when you've got the location data from user, this is the kind of location data will be available to you
array(2) {
["object"]=>
string(4) "page"
["entry"]=>
array(1) {
[0]=>
array(3) {
["id"]=>
int(1151635421536343)
["time"]=>
int(1463265031987)
["messaging"]=>
array(1) {
[0]=>
array(4) {
["sender"]=>
array(1) {
["id"]=>
int(1159277174102575)
}
["recipient"]=>
array(1) {
["id"]=>
int(1151635421536343)
}
["timestamp"]=>
int(1463265031923)
["message"]=>
array(3) {
["mid"]=>
string(36) "mid.1463265031752:07d973ce3f3f276421"
["seq"]=>
int(3531)
["attachments"]=>
array(1) {
[0]=>
array(4) {
["title"]=>
string(24) "What Sweet Hell is This?"
["url"]=>
string(322) "https://www.facebook.com/l.php?u=https%3A%2F%2Fwww.bing.com%2Fmaps%2Fdefault.aspx%3Fv%3D2%26pc%3DFACEBK%26mid%3D8100%26where1%3DSouth%2BBurlington%252C%2BVermont%26FORM%3DFBKPL1%26mkt%3Den-US&h=0AQHaPVgX&s=1&enc=AZPoRntntMTJ6k2Iq9g9uBLH3IFFNySg98jLJEy81cg7zr_ttunOt4DSO9CNdowHocRGLViscMsczdSyYJqtedi8_PT2aHMZgP9FLfAIWDtkuQ"
["type"]=>
string(8) "location"
["payload"]=>
array(1) {
["coordinates"]=>
array(2) {
["lat"]=>
float(44.4493674)
["long"]=>
float(-73.1594363)
}
}
}
}
}
}
}
}
}
}
An example tutorials i found with PHP code Here