This is a great waterproof bag for your 7-8" tablet. I have a 7" ASUS MemoPad, which fit inside this bag perfectly. I did a water test, as instructed by the manufacturer to check for leaks/defects. None found! I can operate the tablet and see the screen easily while inside the bag. I felt confident taking it out on the yak for our trip down the river. The tablet may get a little warm inside the bag due to the fact that it is waterproof, but for short-term use I found no issues of it overheating.
I highly recommend if you want to protect your tablet from being accidentally dropped overboard. Add a key float to the lanyard for a little extra float power.