Nordic Flash Floating Wrist Strap (2-pack) for Phone & Action Camera - Compatible with GoPro Hero 13, Insta360 X4, DJI Action 5 Pro, OM System TG-7, Kodak PixPro WPZ2 & iPhone - Bright Yellow

Most folks here have answered the most important questions. I just wanted to add a few things;; You could go with a waist PFD that inflates into a classic life jacket when you pull a trigger string but since you mentioned ocean I really really recommend a good classic life jacket. There are some aesthetic really comfortable ones out there and id rather be safe than sorry. Pump to the PSI! For phones and other gear my husband and I have two wet bags; one large backpack style that holds most of our gear like spare towel, clothes, etc. Bonus if you get a waterproof cooler for snacks. The other wet bag i have is a cross body that holds our wallets, his phone, and other small items like sunscreen. My phone actually lives separately in a waterproof cases attached to a crossbody strap because i like to take pics on the water. Example strap: https://a.co/d/09rdWotp. Probably overkill but our whole group has at least https://a.co/d/09wuqJyI one of those attached to their phones in the waterproof cases. Re: speaker, obviously be mindful of other people on the water. We went to a few lakes that have partying boaters and jet skiing so on that lake i felt comfortable using my little waterproof speaker attached to my board with a carabiner. I heavily researched one for paddleboarding and came up with the wonderboom speaker that will float if it does get dropped in. For upgrading, we have two bote brand boards but ive been highly recommending retrospec boards to friends because the price is more reasonable. Especially if you want more weight capacity. Beginner tip, explicitly practice falling in and climbing back on your board. We did this at a really calm lake lagoon here in L.A. before ever getting on choppy water. Most importantly, have fun!!

I hope you get a good answer. I’m not experienced with dive cases. But I do know that dive case is very buoyant! Very. I assume the concern is dropping it off a boat while it’s going. You could run a string through that goPro mount. It’s not optimal since they do fail. Sounds like your options are limited. It doesn’t look like you can put a selfie stick on it. If you had time, you could have gotten a converter like this. Converterhttps://a.co/d/00OIt89D D ringhttps://a.co/d/0bJUjVlT Bright buoyant wrist straphttps://a.co/d/02WfrUAX