Waterproof cases for your smartphone is a smart and cheap way to turn your phone into an underwater camera. I use them to take video snorkeling and also protect my phone when at the beach or pool.
There are two brands I have tested and used multiple times snorkeling. JOTO and YOSH sell them on amazon and they both work equally as good. (Links at the bottom of page) Both are under $10.
The waterproof cases fit most phones, even my large Samsung 6s. (Up to 6in long) They are clear cases that you slip your phone into and there is a secure clamp at the top to keep out the water. Your phone can take video and photos from inside the case without affecting the video quality.
TIPS FOR USING A WATERPROOF CASE
Take the “napkin test” before you use your phone with the case. At home, put a dry napkin inside the case and seal the case securely. Then, submerge the case into a sink filled with water or the bath tub. Leave the case there for a few minutes.
Take the case out the water and open it to see if the napkin stayed dry. If so, then you can trust it will keep your phone dry.
Even with the best of brands, it is always possible to get a faulty item so testing with a napkin first is always a safe bet.
If you are looking for a demonstration of the case, you can check out the video I made below while snorkeling at Chileno Bay near Cabo San Lucas Mexico. I also give examples of video from my phone while snorkeling with the waterproof case.
You can purchase the cases on Amazon from the links below with the brands that I have tried and tested.
http://amzn.to/2o8qXBF JOTO Waterproof case in this video
http://amzn.to/2opZayk YOSH Waterproof case