iPhone 8 battery features: Solar
A similar technology category that seems likely in the foreseeable future to supplement rather than supplant traditional battery-charging methods is solar power. Sunpartner Technologies has developed a lightweight skin/case that wraps around a mobile device and collects energy from light that falls on it. This is designed to work with both indoor and natural light, but is obviously better with the latter; in the right circumstances the tech could add some 10 to 15 percent to battery life.
Apple, of course, has been committing itself to a greener approach for some time now, and a patent awarded in 2015 demonstrates this strategy in action.
The patent suggests that Apple is planning to build solar cells underneath the touchscreen on smartphones in future. The panel would recharge during the day and you wouldn't need to plug your phone into the socket any more. Good for the planet, convenient for us. And while unlikely to appear as early as 2016's iPhone 7, this could easily be ready for the big reveal when the iPhone 8 takes its bow in 2018.