You may have seen this video from Samsung where the Galaxy S5 participates in the Ice Bucket Challenge for ALS.
Well someone responded on behalf of both parties. Although not technically waterproof/resistant, they handled things well. Well, they should have. Apparently the 930′s headphone jack got a bit exposed and the phone had to go through the dehumidifier. There are reports of a HTC one working after being submerged in water but others who have tried this note that say the jack and speakers might not work and some saying the whole phone not working at all.
Note that pressure makes a difference too, so if you go into a pool (vs a sink or splashes) you even be less luckier unless your phone is certified or is in a case.