wireless connection

[suzi16]

My son has the latest iPhone. Was ok up until  a couple of weeks ago with data usage. We now have used almost all up. He is able to connect with our wireless but cannot load things like videos. ...it is extremely slow so therefore has not been using the wireless which is resulting in the very high data use. We share 20 between the 2 of us.  This is way more than ever. How can we resolve this? Is something wrong with his phone? My new Samsung Galaxy works just fine

[Weth]

IPhone 6 Has very fast wifi speeds.   Make sure he is on latest iOS update, reboot everything, including phones, router, and cable modem.  Our multiple iPhones have no problem streaming video on wifi.   What is the speed from your cable modem?