I'm revisiting this just to share my experience. My phone was in its ram mount case and the boat capsized. After righting the boat, there was some fog inside the case but the phone was working fine. Within an hour it became too hot to touch and bricked. When i applied for a warranty claim i rolled the dice and said no water damage. Luckily, I got a new one for free from moto, no problems.
After that mishap, I started researching cases some more. I'm purchasing an Armor-X universal. Its rated IPX8 which means its certified to work underwater. I'll post again after I've tried it.
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