FRIEQ® Universal Waterproof Case for Apple iPhone 5, Galaxy S3, HTC One X, Galaxy Note 2 - IPX8 Certified to 100 Feet
http://amzn.com/B00AW2QT8I
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OtterBox Commuter Series Case for iPhone 5 - Retail Packaging - Black
http://amzn.com/B00974L1T4
This good. It's a good idea though.
That's actually cool, the FRIEQ case, but I think the OP was referring to an everyday waterproof case. One that makes it still look like a phone.
You probably wont like my suggestion, but I wanted to get a case like LifeProof, but didn't want to spend $80...
I did some research and a lot of people were buying LifeProof knock offs from eBay, Amazon, etc. The knock off case was actually getting similar reviews as the actual LifeProof case, and people were complaining about the same issues. Some have audio/call issues, and some people don't like the built in screen protector.
I ordered a LifeProof knock off on eBay, $10.99 including shipping. Got the case a few days later, did the waterproof test, and it passed. Threw my 4S into it and I feel so much better about my phone against the elements now. The case adds no bulk and it has 360 degree protection.
As I said earlier, people have complained about the screen protector in the LifeProof, to some it makes the touch screen annoying to use...well I must have gotten lucky because on my knock off case, the fit is tight and you can't even feel a gap between the screen protector and the actual screen. I don't have the "space" between the protector and screen as some buyers do. It feels just like the iPhone screen. I think some are just built more loose than others.
And let me reiterate, I bought the knock off simply to protect it from elements, water, sand, dirt, etc. I didn't buy this case to take into the pool. I will NEVER submerge my iPhone completely in water. But I am 100% confident that my knock off case will make my phone bulletproof to rain/spills/condensation, or any sort of precipitation. I took my iPhone to the beach for the first time yesterday and was sitting in the sand, posting pictures to my instagram. Felt good.