Longer battery life tops many iPhone owners' wish lists, but it could soon become a reality following reports that Apple is secretly developing energy-efficient display technology, Digital Spy reports.

The Cupertino firm has set up a facility in Taiwan where screens for iOS devices will be assembled, according to Bloomberg.

Manufacturing its own displays would pave the way for Apple to lessen its reliance on third parties, such as Samsung and Sharp.

The panels coming out of Taiwan are said to be "thinner, lighter, brighter and more energy-efficient", which should result in improved battery life.

The report also claims that Apple is planning to switch to OLED display technology for 2018, suggesting that the iPhone 8 could be its first device sporting the material.

Apple reportedly has 50 workers operating its new facility, but is advertising for more staff to ramp up production.