An iPhone that got dropped in a frozen lake and remained there for 30days was recently recovered.
Owner Angie Carriere was determined to get back her iPhone which accidentally fell during ice fishing on her 50th birthday. Ironically, this happened after she reminded her daughter to be careful of her phone when the wind blew their tent, and her own iPhone went down deep into Waskesiu Lake in Saskatchewan.
That time she may have thought all hope was lost, but she wanted to get back valuable photos from the trip. Using fish finder and with a group of friends ready to help, she located her lost device, pulled it up with a magnet attached to a fishing line, and the iPhone actually booted up.
It appears in this report that the device is an iPhone 11 Pro, rated IP68 meaning it can survive a depth of water for up to 2 meters for 30 minutes. In this case, it took a whole month in frigid water before it was found.
These events aren’t officially supported by Apple, but there have been a number of similar news in the past where rescued iPhones still surprisingly work after being lost and submerged in water.