Adoption of iOS 7 has been remarkable. According to the New York Times, an estimated 18[ercent of iOS users had downloaded iOS 7 within the first 24 hours. So many people were downloading it that some university networks crashed, and Apple's servers struggled under the load. This strong demand for the new software has led to problems.
The main issue with installation so far has been people getting a message saying "download has failed" after they start the process. You can read more on CNET. Of course the solution is simply to wait until the rush is over or to try downloading it at a time of day when the servers are less likely to be overwhelmed. According to the International Business Times, you may have better luck downloading the update by connecting your device to your computer and downloading the update via the iTunes software. (It's not clear to me why this might help, since I would think it would be the same servers, but it's worth a try.) The article also walks you through the steps of downloading the update directly to your device.
The main complaint is decreased battery life. In fact, iOS 7 does make more demands on the battery than before. But the good news is there are many things you can do to help remedy that. An article on Trusted Reviews outlines steps you can take. They include going to the new Control Center by swiping up from the bottom and turning off everything you're not using: WiFi, Bluetooth, and AirDrop. All of these are constantly searching for available devices, so turning them off if you're not using them extends your battery life. Control Center makes it easy to toggle them on when the need arises.
The article also suggests simply turning down the brightness. In addition, it explains you can turn off some elements of Notifications. If, for example, you don't need stock market updates, there's no reason to have your device using the little bit of energy it takes to keep going out on the Internet to get the latest info. Similarly, do you really need to have your device constantly checking for email? The article suggests you simply change the setting so that it only retrieves email when you manually ask it to do so.
Of course, there are more extreme measures you can take if the problem is so serious that tweaks don't help. The IBT article tells how to do such things are restoring your phone as a new device, which cleans out a lot of stuff that might be clogging your phone, and how to do a "hard reset," which is similar to rebooting a desktop computer.
An article on iMore makes some of these same suggestions. It also recommends once a month completely draining your battery until your device shuts down, and then recharging it. In fact, the article suggests doing this even if you aren't having battery problems as a way of conditioning your battery.
iMore also discusses why in some cases it's better to drop back to 3G service rather than LTE, and that if you're getting a very weak signal, it may be better to switch off your phone access until you're in better range of a tower.
The article explains a range of features that you can turn off. In addition to those mentioned above, you can save power by turning off content refreshing in background apps, Siri's "raise-to-speak" function, and Location services, as well as quitting power-hungry apps.
Atlantic Wire reports that some users are having issues with Gmail and Mailbox resetting their inbox. They say restarting your phone will fix the Mailbox issue.
Finally, someone has already discovered a security issue with the lock screen. You can read more on TechCrunch. By accessing the Control Panel in the lock screen and tapping on the timer button and holding down the power button until Cancel comes up, someone can get access to the Multitasking feature. This then gives the person access to certain camera and social network features. Apple says they're aware of the problem and will be coming out with an update soon.