As report from
Nikkei, Apple partner Wistron has
officially confirmed that at least one of upcoming iPhone models will be
waterproof and have wireless charging capabilities.

Assembly
process for the previous generations of iPhones have not changed much, though
new features like waterproof and wireless charging now require some different
testing and waterproof function will alter the assembly process a bit.

As report from Nikkei, Apple partner Wistron has officially confirmed that at least one of upcoming iPhone models will be waterproof and have wireless charging capabilities.
Wistron is an
Apple partner iPhone manufacturing company that produces iPhone SE and
iPhone 6 handsets in India.

Recently leaked images of an iPhone 8,
iPhone 7s & iPhone 7s Plus indicates that the glass back panels will
feature wireless charging and now Wistron confirms that will be waterproof too.
Via Nikkei