The Apple iPhone 8 remains one of the biggest speculated smartphone releases this year, but its production has been an equally big part of the phone’s rumor cycle. The latest rumors about the iPhone 8 have focused on features both in front and behind the scenes for Apple and its hardware suppliers.

Apple and its suppliers are reportedly having difficulties producing the secondary flexible motherboard that controls the phone's screen, according to a report from China-based Economic Daily News via Apple Insider.

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Among Apple's suppliers, one factory has been unable to consistently produce the component at scale and with consistent manufacturing quality. As a result, Apple is looking to switch this factory out with another supplier from South Korea. According to the report, Apple has yet to start production on its iPhone 7S series of smartphones, but the Daily News also said there are no serious manufacturing or sourcing problems that are causing the delay.

While rumors about Apple’s production sourcing are worth taking with a grain of salt, much of the speculation around the iPhone 8 has focused on various hardware difficulties the company has had for the new smartphone. The phone will reportedly have a number of new features that haven’t been seen on past iPhones, including new hardware sensors and a major OLED screen. Because of this, manufacturers are struggling to iron out bugs from these new pieces and figure out how to produce them at a mass scale before the phone’s expected fall launch.   

These difficulties are also reportedly not limited to the iPhone 8’s hardware. Last month, Apple engineers worked amid “a sense of panic” in developing internal software for the iPhone and some of its new features could miss the phone’s fall launch, according to Fast Company.

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For Apple, these software problems are related to programming that would support many of its new hardware features. The new iPhone has been reported to feature both wireless charging and a 3D front-facing sensor that could potentially be used for high-depth facial recognition or augmented reality applications. But because of continued software development problems for both features, Apple has potentially looked into including a disabled version of the hardware on the iPhone 8 and simply enabling it down the road when bugs are hammered out.

While not ideal for Apple, it wouldn’t be the first time a smartphone manufacturer has included hardware on a phone and left the software for later. As Fast Company notes, Apple previously did the same move with Portrait Mode on the iPhone 7 Plus. Samsung has also done a staggered rollout of its Bixby virtual assistant on its Galaxy S8 series of smartphones. The company is also reportedly dealing with problems sourcing OLED displays at scale for the iPhone 8.