Since September 2013, there were many evidences of the problem
That is, since the launch of the brand new IPhone 5s...
See below some extracts from the discussion:
iPhone 5s sporadically crashing to Apple logo
http://forums.imore.com/ios-7/263115-iphone-5s-sporadically-crashing-apple-logo- 4.html
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"Sooo I've owned every single iPhone since their launch in 2007.
So far, I believe that iOS 7/iPhone 5s has been by far the buggiest.
So here's been my experience... I got a 64 gig gray model on launch day and the problem started happening almost right away. I went back to the store and they replaced the phone b/c of another issue. Then I kept it as new and downloaded the apps directly from the app store. Low and behold the problem started happening again. I then put my old back up on the phone as I knew it was not a problem with the backup.
So I used that second phone for a couple of weeks and dealt with the phone rebooting every day or two. 7.0.3 came out and since it did not take care of the problem I figured I'd call apple care. They went ahead and replaced the phone two days ago and this third iPhone i've owned is also having this problem.
I've done everything that has been suggested from killing background app refresh to reducing motion and the problem still persists. Usually when multitasking or when dealing with an update to a passbook.
So I really believe it's an iOS issue when people us the phone very heavily, or that there is a very common app (like Facebook) that is causing this problem. This is very frustrating and not the type of experience I've come to expect from Apple. I hope this gets fixed with the next release.
OH and for those of you who say it's not a big problem b/c apple hasn't acknowledged it, well, they didn't acknowledge the flaw that allowed people to bypass the lock screen, or the motion/accelerometer issue. They just took care of it via a software fix. Just b/c people aren't complaining or noticing it, doesn't mean it's not happening on a widespread manner."
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I don't get it why Apple put only 1 GB of RAM in the 64 bit 5S. They could have just thrown in 2 or 4GB. Memory is cheap, no matter what Apple say. But maybe even that would have affected the sacred profit margin too much, the margin which is the highest ever witnessed in consumer eletronics, and so now users put up with an underpowered phone. Oh well. Not going to update to 5S myself. Clearly, the design is still immature and just too cheap. A phone that costs EUR 700, or a thousand dollars, should not be crashing left and right because it is running out of RAM. Period.
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My phone has crashed regularly. At least every other day. Safari and multitasking seem to be the biggest culprits. I'm kind of used to it from having a jailbroken 4s for over a year. That phone rarely crashed with stock ios 6. I'm just a little disappointed to see that their new flagship phone and OS are having this issue.