There is a huge distinction between being water-resistant and waterproof. The former is where a device can resist water ingress, while the latter suggests that it is completely immune to any kind of water ingress. For the most part a lot of phones these days are water-resistant, but a recently discovered patent has hinted that Apple might want to take things further.
According to the patent, it appears that Apple has toyed around with the idea of making more of its iPhone components and ports water-resistant and potentially even waterproof. For example it describes how some ports, like the Lightning port, USB-C ports, or other ports on the phone could feature a vacuum sealed connector that will make it harder for water to get inside and thus damage internal components.
Apple notes in its filing that as smartphones become more ubiquitous and essential in our daily lives, that they’re finding their way into harsher environments, which means that they might need even more protection than ever. It sounds like an interesting idea, although unfortunately given that it is a patent, there’s no telling if Apple ever plans on making it a reality.
At the moment the iPhone XS and XS Max feature an IP68 rating. This means that it is resistant to dust, dirt, and sand, and can also withstand submersions underwater of depths up to 1.5 meters for up to 30 minutes. This means that it is good for times you accidentally drop your phone, but not necessarily good enough to go deep sea diving or swimming with it for extended periods of time.