Last week, there were reports suggesting that the next iPhone probably the iPhone 8 will come in three size variants with the addition of a 5-inch display size model and all glass body design. Today, reports from the same source i.e. Nikkei Asian Review are coming up that Apple might introduce OLED displays at least in the 5.5-inch model. Further, Sharp might produce it for Apple this time.
Back in August 2016, Foxconn acquired Sharp and Tai who is a close associate of Chairman Terry Gou, was appointed as CEO. For those who are not aware, Foxconn is Apple’s primary manufacturer for iPhones. 
Tai, CEO Sharp, at a ceremony at Tatung University told students that – “The iPhone has been evolving and now it is switching from LTPS (low-temperature poly-silicon) to OLED panels,We don’t know whether Apple’s OLED iPhones will be a hit, but if Apple doesn’t walk down this path and transform itself, there will be no innovation. It is a crisis but it is also an opportunity,”
OLED displays are said to be sharper, more vibrant and pleasing to the human eye and a lot of handset manufacturers such as HTC, LG and especially Samsung have been introducing OLED displays in their smartphones. Samsung is known to include Super AMOLED displays on almost all of its mid-range to flagship devices. Apple too introduced OLED displays in its Apple Watch last year.
Further, Sharp being one of the manufacturers of this OLED displays, there is a possibility that a part of the manufacturing is done in the USA itself. Usually, Apple likes to get its components (including the displays) manufactured from multiple suppliers.
Recollecting other rumours, Apple is also expected to ditch the newly introduced touch button for a button implemented underneath the glass. Of course, the button will come with Apple’s Touch ID.