Im at CN right now and notice that some of those fantastic couples floating mats seem like they are brand new (yea! There are plenty). However if use the new spray-on sun block that contains a fair amount of alcohol, here's a word of warning. The alcohol in this stuff will transfer the ink from the mats to your skin...you can end up with a smeared mat and blue ink circles on your back! The solution is to either turn over the mat so the logo faces down, or put a towel between you back and the mat. Have fun!
We learned this too when were at CTI last year. My husband ended up with a temporary Couples logo tattoo on his back! It was pretty funny!! Like you, we turned them upside down before laying on them from that point on!
The newer sunscreens will also cause the coloring to start to wrinkle and peel off on your cell phone covers if they are the harder snap on plastic type. I ruined 2 of them last summer this way. These were not third party knockoffs but straight from the Verizon Store. Go with the softer gel looking ones that are not painted. I guess those with tablets should look out for this as well.