I've had quite a journey with my iPhone 6 devices. Yes, that's plural. Got my new iPhone 6 in Sept/15. In January, it started randomly rebooting itself when it wasn't being used. When it powered back on, the wifi was disabled and not able to be toggled on. I was able to get it working again by the usual steps--turn phone off, then on, home/off button reset, reset network, reset all settings...Over the 3 month period, there were chats with Apple support and a visit to the Genius bar, where no hardware issues were found. I was advised to restore the phone using iTunes. Eventually, it came to that, as the reboots increased in frequency and the efforts to get the wifi back had to become increasingly aggressive. One day, the bluetooth also stopped working. I restored the phone to factory specs using iTunes. The Wifi and bluetooth remained nonfunctional. The phone was replaced under warranty. I've had the new iPhone 6 for 31 days now, this is day 32. On day 30, it lost the cellular network. Lots of the usual troubleshooting steps to try to bring it back, hours on the phone with Apple tech support. I am now in a rural area with a satellite internet service, so restoring with iTunes is pretty difficult, to say the least. The service came back for nearly 24 hours, then quit again. In the middle of the night and with spouse's iPhone 6 data plan and hotspot, I was able to do the restore of my phone with iTunes in about 2 hours (as opposed to the 30 or so the satellite service would have taken). The cellular network was back, I restored my stuff from a backup on my computer and went to bed. This morning I awoke to no cell service. But through a bit of toggling this and that, I can get it back, and it's there now...but could be gone in 2 seconds. Or minutes. Or an hour. The SIM card works just fine in my iPhone 5. Works beautifully. In the 6, it is unreliable now. I am waiting for my Apple tech to get back to me. I have had him reopen my support case and emailed him details of everything I have done. I am in a rural area now with no easy physical access to Apple techs. I was in a large city with access to a Genius Bar when the first phone malfunctioned. It has been suggested to me (by a non technical person) that since I have had issues with 2 phones it a row, it must be something I am doing. (Never mind that my iPhone 5 always worked flawlessly. If it hadn't, I wouldn't have stayed with Apple.) I have never dropped my phone nor gotten it wet. It is in a cover. I am a retired lady, my phone does not see rough usage. The phone is not jailbroken. All apps and the OS are updated. I think it is reasonable that I can expect to be able to use my Apple apps on my Apple phone. I read. I take pictures and videos. I use a browser, I use Facebook and Messenger, I get email with the native mail app, I listen to purchased music. Oh, and I text, use iMessage. And make the occasional phone call, LOL! I have some other apps that are pretty low demand...not powerful gaming apps by any means. The hotspot has barely been touched...haven't really had much chance to. In fact, I don't think I have used it at all. The hotspot in my 5 got used a LOT. I don't think I am doing anything unreasonable or wrong with my phone. My phone is a gold model, 64 Gb. Are these known to be a problem? I'm waiting for my Apple tech to contact me...my SIM card has some rub marks on it and I'm wondering if he is leaning toward blaming the SIM card. But the SIM card works great in the 5. I left it in there for a few hours to try it, and it didn't quit on me when it was in the 5. I even used the 5 as a hotspot for my computer last night when a storm on the east coast knocked out my satellite internet service for a while. Not a glitch. --- Post Merged, Apr 27, 2016 --- At the moment, cellular service on the iPhone 6 randomly cuts out. The last time it did it this morning, I just left it alone and it came back on its own. I am resisting the urge to do anything more with this until I hear back from Apple. I had posted a thread here before asking about the wifi turning off when the lock screen was on. When I would pick up my phone and tap the home button to show the lock screen, I would see the 3 G on and not the wifi. The wifi was actually a bit slow to come back even once I got out of the lock screen. Since I did the restore last night, that is no longer happening with this phone. The wifi just stays on. The battery is going down pretty fast. In 4 1/2 hours I'm down to 73%.