I believe IP ratings are for "resistance" (for a certain depth/period of time). Water "proof" means completely impervious to water, period.

I don't believe any phone is water proof.

There's a pretty good writeup of the IP ratings, how to interpret them, and how they compare with other phones here:

http://www.pocket-lint.com/news/138727-apple-iphone-7-and-7-...

From your link:

Waterproof

• Down to 1.5 m • Max 30 mins • IP rating 65/68

This is _not_ water PROOF.