Apple's iPhone, with its ability to surf the Internet, access multiple email boxes and make use of thousands of applications, is a technologically advanced device. It isn't, however, invincible. One situation that can severely compromise your iPhone's function is getting it wet, whether from excess humidity or moisture, or dropping it in water.
Dry it Out
The first step you should take before going to any additional lengths to remedy your wet iPhone is giving it time to dry out. This is especially valuable if your iPhone was simply exposed to excess moisture or humidity, which could happen if you left it in the bathroom while you were showering. Turn off your iPhone, place it in a warm, dry place for at least three hours, then attempt to power on the device.
Take your water-damaged iPhone to an Apple store or contact Apple support to locate an authorized repair center near you. Even if the repair isn't covered -- as water-related damage officially isn't, according to Apple's website -- Apple can repair your device for a fee. Note that if you've "unlocked" or otherwise modified your iPhone to be users with other carrier or third-party applications, your warranty is void, regardless of whether the water damage is covered.
Private Repair Specialist
If your iPhone isn't under warranty, you don't live near an Apple store or authorized repair center, or you simply don't want to seek help from Apple, you can always hire a private repair specialist. Only consult the help of specialists who advertise experience with Apple devices and specifically iPhones. If the technician isn't Apple-certified, any modifications he makes to your iPhone will void your Apple warranty.
Using a Water-Damaged iPhone
If the water damage your iPhone suffered doesn't prevent it from turning on -- or performing other major functions -- and you don't want to pursue repairs or can't afford then, simply use the iPhone in spite of the damage. If your screen fogs up from time to time, for example, simply do the best you can navigating around it. If your speaker or microphone have been reduced to partial function, use an alternate option for making and receiving calls.