My Wi-fi is on and I'm connected to my network but my phone is still running on LTE. I tried turning wi-fi off and reconnecting to my network but it still says LTE. I know it's not an issue with my network because an iPhone 4 that we have is connecting to wi-fi just fine. Is anybody else having this issue?
Try turning Airplane mode on and then turning it back off. It's not an idea way to have to "fix" the issue, but it should trigger the wifi back on. Also make sure you report the issue to Apple via their website. It may be an issue they need to address with the next update.
Devices Are programmed to connect to the strongest signal..I would turn your mobile data off when you are going to be on wifi so it doesn't compete..they may not be able to truely ever fix this with software, my droid x did it all the time