If you check $_SERVER['HTTP_REFERER'], you can get the device. It is human readable, but you do need to look:
20160101002707, /Coach-Karl.php, 98.180.178.34,
Coach-Karl.com - Naked Muscle on Home DVD and eBooks, ^ Mozilla/5.0 (Macintosh; Intel Mac OS X 10_11_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.106 Safari/537.36 |98.180.178.34,US,United States,NV,Nevada,Las Vegas,89169,America/Los_Angeles,36.17,-115.14,839
20160101204451, /index.php, 66.249.64.31, , ^ Mozilla/5.0 (iPhone; CPU iPhone OS 8_3 like Mac OS X) AppleWebKit/600.1.4 (KHTML, like Gecko) Version/8.0 Mobile/12F70 Safari/600.1.4 (compatible; Googlebot/2.1; +
Googlebot - Search Console Help) |66.249.64.31,US,United States,CA,California,Mountain View,94043,America/Los_Angeles,37.42,-122.06,807
20160107134147, /PolandJocks/ThePolandJocks.php, 86.204.176.36,
The Poland Jocks - Naked Muscle from Waersaw on Home DVD and eBooks, ^ Mozilla/5.0 (Mobile; Windows Phone 8.1; Android 4.0; ARM; Trident/7.0; Touch; rv:11.0; IEMobile/11.0; Microsoft; Lumia 435; Orange) like iPhone OS 7_0_3 Mac OS X AppleWebKit/537 (KHTML, like Gecko) Mobile Safari/537 |86.204.176.36,FR,France,D,Bourgogne,Fixin,21220,E urope/Paris,47.25,4.97,0