Apparently, it's not too early to talk about Apple's 2018 iPhones

Kuo believes Apple will launch three new iPhones in 2018. Two of them will sport OLED displays, while the third will come with LCD panel. Size-wise, the OLED-based iPhones will boast 5.8-inch and 6.5-inch displays respectively, while the bezel-less LCD model should sport a 6.1-inch screen.
The analyst had something to say about Apple's upcoming prices, but he only referred tot he LCD-based model. According to Kuo, the 6.1-inch iPhone will cost $649-$749 in the United States, but these are just starting prices.
We believe the major hardware difference in the two new OLED models is size, in a bid to satisfy various needs of the high-end market. The new TFT-LCD model will differ significantly from the OLED models in hardware and design specs (for instance, the PPI will be lower). The primary selling points of the TFT-LCD model may be the innovative user experience of an integrated full-screen design and 3D sensing with a lower price tag (we expect it will likely be US$649-749).
source: MacRumors
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