iPhone presence detection

[DGrandes]

Hello,

I´ve tried this script but it doesn´t work if iphone is locked. When I unlock if work perfectly.
With android devices it works perfectly.

Any Idea?

Thanks

Code:

function checkiosdev(ip)
 local sock, res

 sock = require('socket').udp()
 for i = 1, 10 do
   sock:sendto('123', ip, 5353)
   os.sleep(1)
 end

 res = os.execute('ping -c 2 -W 10 ' .. ip)
 return res == 0
end

seen = checkiosdev('192.168.1.10')
grp.update('1/1/1', seen)