A few things:
1. Please ignore users that state this is no big deal and that we are being OCD etc. This is clearly a problem for those of us that use apps using the gyro/accelerometer. My Xplane always veers to the right and I have to calibrate within the app every time I launch it. Some apps don't have this feature. If you respond or argue with these users no matter how wrong or patronizing they are, the moderators will close the thread just like the original.
2. As bad as it is for some, I think the best course of action is to contact Apple and let them know so they will be more aware of this issue. Since most of the phones have this issue trying to go through all the hassle now to get a replacement that may be a little better or worse is just not worth it esp if you phone is perfect in every other way.
3. I feel apple will do 1 of 3 things with this
-Fix it in the factory and just replace iphones at peoples request.
-Give the genius bars a low level software calibration that can calibrate the phones if the are brought in.
-Add a user calibration option in a future software update.
Unfortunately since Apple doesn't like to admit its mistakes we may see the first option. The average person doesn't even know what a gyro/accelerometer is and would prob not notice it being off so I doubt Apple would announce it and cause a huge hardware swap out or even go to the trouble to code in a user calibration option.
I just find this disappointing because the previous phones were 0 and one of the big features of the 5S is the "motion" chip which is clearly less accurate.
As far as the image in the manual that just showing you how to use it. That doesn't fix/calibrate it. I can put it at any angle and tap the screen to make it 0 green but it still not correct with reality. I can't use my iPhone to hang a picture frame like stated here because it will be off 3 degrees. IPhone 5 was fine for this. (I know use a real leveler but the iPhone 4,4s, and 5 worked fine for this)
Read the manual and found this if you guys have not noticed it yet. Just a bit of information.
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Worth a try. Ill do it to the second phone now before I send back to ATT. Somehow I believe this person was blowing smoke as that is an odd way to calibrate it but ill try anything. Unless the do not disturb mode triggers calibration as I have mine plugged in on a flat surface every night and no change.
Just got a call from apple. This is a recommended solution for this problem. I will be trying this before going to sleep this evening. If others want to give it a go today, please update with the results...
Turn on "Do not disturb"
Plug it into the wall charger
Do not touch the device or turn on the screen, really dont mess with it!
Let it sit untouched with do not disturb on for over 90 minutes.
I was told that this should recalibrate the sensor. We shall see...