For those who have the new iPhone 5s, you might encounter, at times, inaccuracy in the accelerometer (leveling out). This might be evident in games that require this sensor to perform some functions. You are not alone.
Bad news is that this is a hardware issue. Good news is that someone (not Apple) is going to help out with a fix (software). From Gizmodo, Apple is not commenting on this issue when asked.
So, what is the problem? According to the source, Apple changed the maker for this accelerometer sensor. The iPhone 5s (I presume iPhone 5c too) is now using Bosch Sensortech accelerometer instead of STMicroelectronics part.
They have different specs and in layman term, it means a wider specs of +/- 5 degree as compare to ST Microelectronics component which has a spec of +/- 1 degree. Click here if you are interested in the technical part.
RealityCap will be helping developers to overcome this issue. They mentioned in their blog that by calibrating the sensor prior use, users are able to compensate for the inaccuracy. There is no timeline for the fix.
Click Here to Read from RealityCap blog post
This shows the importance of choosing each component in a device. In the past, Apple has been doing a good job. Not sure why they did not check thoroughly (my presumption again) in this case.