Larger devices could help counter competition from Samsung, HTC

Apple Inc suppliers in China will begin mass production of its largest iPhones ever next month, according to people familiar with the plans, as the smartphone maker faces increased competition.

The tech giant is ramping up on two bigger devices, said the people, who asked not to be identified because the plans are private. One model will have a 4.7-inch display, compared with the 4-inch screen of the current iPhone 5s, that may be available to ship to retailers around September, said two of the people. A 5.5-inch version is also being prepared for manufacturing and may be available at the same time, the people said.