Where to Put Your Phone and Key Fob While Open Water Swimming

I take open water swim lessons and often get asked what I do with my valuables while I'm out in the ocean. While you can leave them on the beach (I've never had anything stolen that way) I prefer to carry my phone and key fob with me. I've tried some other water proof cases which work fine for just a phone but are not big enough to carry both. The AquaVault Waterproof Phone Case fits both (I have an iPhone SE). They are $35 and you can buy them online here: