My max range seems to be only 100 feet

I bought one of these yesterday and tried it out and it seems the range on it only seems to be about 100 feet outdoors with nothing in-between the phone and the cat.  I tried changing the battery and that didn't help.  I then exchanged the device for another one and I have the same problem.  I have a decent phone, is there anything on there that I can adjust to improve the range?