Apple’s iOS 8 was just released, and as with most initial releases, it has not come without a few bugs. While the OS includes a number of new features like the QuickType keyboard, once installed some people are finding some small issues with VPN connections, inability to access voicemail or enter iCloud keychain verification codes, and videos not playing in Safari, among others. However, two issues that appear to be outstanding are Wi-Fi connectivity problems where systems are hanging or running very slow when connected to Wi-Fi, and having exceptionally short battery lives.
Rumor has it that Apple is tackling at least a few of these with the upcoming iOS 8.0.1 update; however, in the mean time you have several options you can try for fixing these two issues:
1. Reset iOS network settings
Go to Settings > General > Reset, and select the option in the middle to Reset Network Settings. This will clear out the current Wi-Fi connection setup and start it over fresh, and hopefully allow your iPhone to establish a more robust connection with your Wi-Fi base stations.
Unless you use them, ensure special Wi-Fi features are disabled. One of these is Wi-Fi calling for T-Mobile which can be toggled by going to Settings > Phone > Wi-Fi Calls. In addition, iOS 8 includes the option for iPhone Cellular Calls that can allow phone calls to be accepted and made on iPads and Mac OS systems (running OS X Yosemite). If you have enabled this feature and do not use it, then you can turn it off by going to Settings > FaceTime.
1. Restart your iPhone
Of course this is perhaps the first thing you have tried; however, if not, then restart your iPhone or iPad by holding down the power button until you see the slider to turn it off, and then drag the slider to the right to confirm shutting it down. When powered off, press the power button again to turn it back on.
2. Disable background refreshing for apps
Go to Settings > General > Background App Refresh, where you can globally disable the ability for running apps to update in the background. If you see battery improvement with this service off, then enable it and try troubleshooting by disabling background refresh for specific apps.
3. Disable Handoff
Go to Settings > General > Handoff & Suggested Apps and turn this feature off if you do not use it.
4. Disable Location Services
In Settings > Privacy > Location Services, you can similarly turn this service off globally, or do so on a per-app basis. You can also disable sharing of your location through with the current device. Any of these settings may cause your iOS device to work more in the background, and result in extra battery drainage.
5. Disable Wi-Fi and Bluetooth
Finally, if you do not use Wi-Fi or Bluetooth features on your iOS device, or only do so rarely, then disable them by swiping up from the bottom of your device’s screen to reveal Control Center, and then tap the icons to disable these services.
These steps are not guaranteed to fix your iPhone’s Wi-Fi and battery issues, but since they do not affect all iOS devices, chances are these problems are from a configuration issue more than from an inherent incompatibility between the software and specific hardware. These steps should toggle or reset relevant services and hopefully get your iPhone or iPad behaving properly again.