Having just recovered the MacBook Pro that was inadvertently filled with water, it's time to move onto the equivalent iPhone. This one fell into the loo, which apparently is a more common situation than one might imagine.
The rescued dead phone was handed to me to fix. The basics are:
1) Power it off by holding down the power and front buttons for 4 seconds.
2) Remove the SIM, so that more air can get inside.
3) Put it in a ziploc bag of uncooked rice.
4) Place it on a warm to hot radiator.
The 'power it' off step is slightly futile, because if it was on when it hit water any shorting out will have already occurred. The remove SIM is mainly because the space created improves airflow. The rice is something that readily absorbs water, like those little bags of silica gel sometimes in the packaging of electronic devices. The radiator is to heat up the innards and hopefully assist recovery.
Leave 24 hours and it should all be back to normal.
If it doesn't recover, there's still a good chance that the iPhone will be readable in iTunes. That's because the screen is the most likely piece to fail, which doesn't affect the rest of the operation of the device. If so, back it up - it can be recovered to another device.
In this case, normal service has been resumed.
