Security issuesThis last update added more security options, but the security options really don't make much of a difference. If your device is stolen your information is still compromised, if someone gains access to your ICloud account your information is still compromised too, the best thing you can do is turn off icloud sync if you don't want contact or photo's being stolen. The real reason for this update was for security issues with their ads, and to let people know what contains ads due to a new law passed in UK that forces people to be informed of the usage of their cookies. While ads still collect personal data, and personal information on Iphones, they managed to work around this with a general disclaimer with this patch. The update didn't solve any of the "mailware" issues, just a rebranding phrase of viruses obtained from emails(apparently according to apple fanboys it makes it different somehow). At least this put more of a foot down on advertisers stealing information, now all they have to do is putup a generic disclaimer which does nothing.
Photos bugsThere have been nemerious sync bugs with this last update, one of which prevents you from deleting your photo's, you have to unsync, delete photos, resync, delete photos again, then unsync to solve this issue. Deleting them from your phone or on your computer doesn't make a difference it needs to be done this way.
Best option is to not sync it with your ICloud and to use things like google docs instead or some other third party cloud storage.
Suppending Freezing issuesMany applications are getting feedback now that claim their app is causing their IPhones to lock up and freeze, this isn't the applications actually. There is several OS level issues going on now with Iphones with supending apps which it does now when ever the phone goes into lowpower mode, or is set into sleep/hybernation. This suppending mode has various bugs that cause the Iphone to lock up and the only thing that can be done is mannually turning off by holding down the power button for several minuets.
Phone lockups and memory issues with appsThe newest update has some new form of memory management with suppending applications, this update was for "security" just like everything else in this update apparently. But what happens often is a application that is suppended eats up memory and eventually causes the phone to lockup because all of its processes are being halted by a single thread of hanging memory from a suppended application, when ever you don't use a application that is open for a while or until another needs more RAM it takes the oldest application and dumps the ram it is using causing the application to basically restart. This memory management has caused lock up issues causing applications themself to lock up when they are restarted not all the time they are loaded properly due to it dumping some of the memory not all. This isn't the applications fault it is the updates. You most of the time have to end the application and restart it mannually.
With these new patches there have been orientation bugs with the keyboard, with photos, and with appilcations. What is going on is with the new update they also messed with orientation for what ever reason trying to make it "smoother". Often you see the keyboard bugging out with this the most, but images get streteched out and so do applications as it trys loading the previous orientations image but the phone stretches it to fit. Again not application issues as it is the OS level not sending out the correct orentation signals to the applications, it happens based off when and how you rotate the device such as just unlocking it or switching apps. The keyboard it happens to the most. With the newest update the slightest bit of change of angle can trigger a orientation swap even going into the wrong ones. There is no fix for this problem other than flipping your phone around till it fixes itself if you are lucky. It happens AAAAALLLLOOOOOTTT. Best solution is to turn on orientation lock but then you can't use landscape which is nessary for gaming but apple doesn't care they only made everything in portait view for their stuff.