JOTO waterproof pouches
The default waterproof pouch — IPX8, widely reviewed, cheap.
Modern phones carry an IP68 rating, which covers a drop in the bath and not much else. It's tested in still fresh water, it degrades as the seals age, and water damage is excluded from most warranties. A sealed pouch is what you want for salt water, sand, or a genuinely wet day.
Protects against salt water and sand, which IP ratings don't. Touchscreen works through the window. Most designs float.
Photos through the window are noticeably softer. Face unlock usually fails through the plastic. Cheap seals fail.
Test every new pouch empty first: seal a tissue inside, hold it under water for a minute, check the tissue. Two minutes, and the only way to know before your phone is inside.
The default waterproof pouch — IPX8, widely reviewed, cheap.
For the beach, the kayak and the building site — where an IP rating isn't enough.