5 - 30 minuten
My son dropped my iPhone 4 in the pool. It shut down immediately by itself, and on the advice of friends, we stuffed it in a bag of rice for a few days.
When after a few days, we tried to restart it, the battery was dead, so we plugged it into a charger. It started, but there appeared to be some small spots on the display, the phone kept restarting, the battery wouldn't take a charge and the wifi didn't work. Didn't try to make a call, because the month-to-month plan had expired and I didn't want to pay the bill until it was working.
I wasn't sure it had dried out completely, so I ordered a cheap repair kit online to take the back off. When I did this and took the battery out, I couldn't see any moisture, but I left it open all day with a fan blowing into it.
When I was certain it was dry, I plugged it in again. The spots in the display were gone and must have been moisture, but the battery still wouldn't charge and the wifi wouldn't work.
I wouldn't have thought the battery had anything to do with the wifi, but when I took the battery out of another iPhone 4, and swapped it in, everything worked. So I ordered a new battery from iFixit. It was easy to install and even came with tools and new screws which was nice because I think I had damaged the old screws from removing them several times. The battery was a little more expensive than some of the others I found online, but seems to be of excellent quality. Reading the Amazon reviews, it seems a lot of people were unhappy with the really cheap batteries they bought.
It seems that getting an iphone wet doesn't necessarily kill it, but the battery usually doesn't survive. It's not a difficult process to fix it. Don't get a new phone.