Wifi now not working on my MacBook Air or IPhone after update

My wifi connection was always incredible before I updated my iPhone 4S and my MacBook Air with the most recent update (my air now runs 10.8.5). But now whenever I try to access the internet on either it works for about the first 30 seconds and then stops running. Both devices are connected to the wireless signal but nothing is loading until I turn the wifi on and off and reset the connection. Again it only works for 30 seconds to a couple minutes. Should I uninstall the new software?