AppleInsider notes that Apple has done this before with the iPad. The A7 processor on the iPad Air is clocked at 1.3 GHz; whereas, the A7 processor on the iPad mini with Retina is clocked at 1.29 GHz.
Arcuri also said that the processor in the 5.5-inch model could ship with a larger die, hinting at a more wide-ranging architectural split. A larger die might be a sign that the 5.5-inch model will feature additional on-die silicon, such as a larger array of graphics processing cores. Alternatively, it might suggest that Apple will make the two chips — believed to be the "A8" — in different fabrication plants using different processes.
The analyst also said that the iPhone 6 models could feature different touch modules.
Apple is expected to unveil the iPhone 6 in mid-September; however, it's unclear if the company will debut both models at the same time. Some speculate the larger 5.5-inch iPhone 6 could launch later in the year.
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