Images claimed to be of the iPhone 6S Plus have leaked online, showing internal changes that suggest Apple has improved the strength of the phone.

One of the changes Future Supplier has revealed is that two screw holes have changed position, one of which is for the loudspeaker module, which could suggest a switch to a new speaker module. The current iPhone 6 has been rated the loudest iPhone yet, but these changes could mean the iPhone is about to get even louder.

Speaking to the website, a source said: "The iPhone 6 Plus’ rear housing feels smoother than the iPhone 6S Plus, while the 6S Plus’ rear housing is stronger." Apple received strong criticism upon launch of the iPhone 6 for a reportedly weak housing, which could lead to phones bending when pressure is applied.

The ensuing controversy, known as "bendgate," dominated tech news headlines. Foxconn CEO Terry Gou said to Macworld UK that the saga was a non-issue. "How can a phone bend? This was all caused by distortions from competitors. Don't blindly listen to it," he said. However, if the leaks are true, this could mean that Apple agrees with its critics that the phone could be stronger.

Previous rumors have suggested the iPhone 6S would retain the same basic design as the iPhone 6, in a similar fashion to previous iPhone launches. Apple typically only changes the design of the iPhone every two years, with the "S" upgrades focusing on internal changes over cosmetic updates.