Mikey Campbell
A potential bug discovered in Apple's latest iOS 9 release appears to be impacting certain apps running on iPhone 6s that tap into compass and gyroscope data, in some cases affecting key assets that render some features unusable.
AppleInsider reader Frank experienced the problem first hand with popular stargazing app Sky Guide, which relies on iPhone's advanced sensor suite to power an augmented reality function that transforms the device into an interactive map of the night sky. Under normal conditions, users point their iPhone up toward the sky to see an onscreen view of stars, planets, constellations and more, but on iPhone 6s running iOS 9 — including the latest iOS 9.0.1 update — the map drifts uncontrollably.
Developer Fifth Star Labs confirmed issues affecting Sky Guide's "Compass" feature are limited to iPhone 6s and do not extend to older hardware. Other augmented reality titles relying on data generated by iPhone's digital compass, three-axis gyroscope and accelerometer are also seeing problems, but certain apps like Apple Maps function correctly, suggesting the issue lies in a faulty iOS API. Fifth Star Labs is currently working on a fix.
Apple faced similar sensor difficulties in 2013 when iPhone 5s owners reported faulty readings from iOS 7's Compass app. At the time, some assessments claimed Apple failed to properly employ an appropriate firmware calibration bias when it switched from accelerometer supplier STMicroelectronics to Bosch.
Extremely sensitive components like those employed in iPhone are notoriously difficult to integrate due to wide ranging hardware variance and bias specifications that differ by type and manufacturer. A seemingly minor discrepancy might result in pronounced deviations for apps tapping into iPhone's data feed.
According to iPhone 6s and 6s Plus teardowns, the handsets use the same InvenSense 6-axis gyroscope/accelerometer chip and Bosch Sensortec 3-axis accelerometer module found in last year's iPhone 6 lineup. Upgraded from last year is the M9 motion coprocessor, now embedded in Apple's A9 SoC, which acts as a data hub for iPhone's various sensors, including the accelerometer, compass, gyroscope and barometer.
Update: Sky Guide has been updated with a workaround for the Compass feature issue.
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22 Comments
I noticed this yesterday with the same app. Tried Maps and the compass worked fine.
This might be what is causing the jerkiness when I use the Maps app when driving and it's just tracking my location. Noticed it on the iPhone6S Plus on the weekend. Looks to only update the screen once a second rather than how it used to be smooth.
I'm not sure it's just the 6s. My 5 told me the blood moon was at least 35° elsewhere than it really was.
Wait a second.... how does this: ...but certain apps like Apple Maps function correctly, [B][I]suggesting the issue lies in a faulty iOS API. [/I][/B] ...allow this? [B][I]Fifth Star Labs is currently working on a fix. [/I][/B] Either it's an iOS API bug and Apple is tasked at fixing it OR the developer needs to go back and integrate what is in the iOS API and then fix his/her app. No developer can FIX Apple's API's for them... AFAIK.
Tried to use Sky Guide last night but it kept drifting to the north no matter what direction I was facing. Star Walk and Star Walk 2 performed flawlessly for me. Unfortunately we had clouds and rain so I missed the eclipse anyway.