The iPhone 6s isn't waterproof, but that doesn't mean that Apple didn't put additional effort into protecting it from the elements. iFixit, known for its repair guides and device teardowns, opened up Apple's latest phone once again to investigate its potential water resistance.
iFixit found adhesive around the iPhone 6s display, which they say wouldn't have been necessary to keep the display attached. iFixit believes that it could function as a gasket, keeping liquid out, rather than keeping the display on. They also found that every cable connector on the logic board had a seal.
Every cable connector on the board—from the battery and display, to the Lightning port and buttons—is surrounded by what appears to be a tiny silicone seal. Those little connectors are the most vulnerable bits of the device—quick to short out and corrode during unplanned aquatic excursions. Apple filed a patent for waterproof silicone seals on board-to-board connectors just this past March. It appears this is one patent they've rapidly put into production.
All of this doesn't make the phone waterproof. Other parts of the 6s, including power and volume buttons, have been redesigned to be waterproof, for instance. However, the added water resistance means that you might not have to get your phone repaired or replaced the next time you accidentally drop it in a sink.