Unfortunately, this can happen to the best of us. Sometimes during the busy and stressful times, we tend to forget and then disaster strikes. So first thing first. Don’t blame yourself. You are not the first one to have dropped an iphone in water.
The first order of business is to make sure that you get the device out of the water immediately. Please resist your temptation and DO NOT Plug the device into power or DO NOT attempt to turn it on to check for damage.
If the device is in a case, take it out along with the SIM Card. If you are hands-on type person, go ahead and take the battery out of the device as well. You can look in youtube for scores of videos showing how to take the battery out of the phone.
Wipe the device down to remove water and turn it on both directions so that any water in the ports can come out. This is especially important if the phone was damaged by salt water as salt tends to corrode the internal circuitry of the device.
The next order of business is to get the phone dry. The best tip is to get silica gel packets. Cover the device with Silica gel packets and set it out to dry in an airy cupboard. Some folks swear that using dry rice helps in removing the moisture. The risk with that is that it can add dust etc to your device. Your best best is to use the Silica gel packs. Once the device is dry, you can try to get it started by switching it on. Remember to put the battery and SIM card back.
If the damage is extensive, you will need to head to an Apple Store. Unfortunately, Apple doesn’t cover warranties if there is liquid damage to the device. . The devices have internal liquid indicators, so please do not attempt at making up a reason for your device not working. The same is true when trying to sell this device to Gazelle or other places. The water damage will be discoverable, so please keep your integrity standards intact.
Liquid damage is often irreparable. If you do not have the iTunes back-up, you can try to use a third party program such as iOS Data Recovery to recover your data from the phone but if your phone doesn’t power on this will not help. Some users have suggested replacing the battery and giving it a try, but we recommend that you take your phone to an authorized Apple Store and have it checked out. You can also look at tips around restoring water damaged electronic devices at ifixit. You can also check with companies such as Mobile Ease to evaluate the extent of the water damage to your device.
This is one more reason to make sure that you have regular back-ups of your device and invest in a waterproof case for it.