Here's why the Apple iPhone 5s' accelerometer is off
A little over ten days ago, wereported on what turned out to be a widely publicized issue with thenew Apple iPhone 5s – it's accelerometer. It'sbeen reported and confirmedbeyond a shadow of doubtthat the sensor is way off, though the exact cause split thecommunity of unhappy Apple customers in two: some suggested that it'sa software-side thing, while the rest argued it's the hardware.
Accordingto RealityCap CEO and developer Eagle Jones, its the latter that hadit right all along. As we noted in our previous report,Apple has gone ahead and switched its partner for the precisiondevice from STMicroelectronics to Bosch, which would've been a-okay,but as it turns out, the new part actually appears inferior. Beforeyou understand why, it's helpful to understand that accelerometersrely on two key measurements to showcase the level of theiraccuracy: bias and variance. The former describes the level ofconstant inaccuracy stemming from the hardware process, while thelatter simply rates the consistency of an accelerometer's readings. Jones further explained this in an e-mail toGizmodo:
Allfine and dandy, but it would appear that while variance for the twoproducts is almost identical, the bias values differ greatly:
Meaningthat iPhone 5s' equilibrium measurements can be off to a pretty wide margin if you're unlucky and get a more extreme case. What's more,Jones told Gizmodo that Apple could have actually compensated for thischange with further factory calibration, but for whatever reason –they didn't. Luckily, according to Jones, this can still be salvaged,though the work-around and this whole issue will definitely serve totarnish Apple's image of shipping products that just work from theonset:
What'smost disappointing, though, is that we still haven't heard of Cupertino on theissue, which is probably smart on their end. That's not to say that it's not important– anything from gaming, to use of any tools and apps that takeadvantage of your iPhone 5s' accelerometer, down to the touteddedicated M7 chip can and will be affected.