I want a wrist-wear gadget that counts the laps I swim. It's tedious counting laps. All this gadget has to do is increment a counter each time I make a 180 degree turn. And of course it has to be waterproof. There's a market for my gadget! The closest thing I can find is a thingy you stick, underwater, to the end of your pool. You press its big button each time you pass it. If you search for "lap counter" and "waterproof". you'll find some even lamer solutions to my problem. Why should I have to press a button? Let the gadget figure out that I'm turning around!
UPDATE! My commenter (THANKS!) pointed me to exactly the device I want. It does count laps by sensing turnaround, and it does a lot more. It's called the Clothing+ Swim Distance Tracker, and it is available (for now?) only in Finland? I've got to get one.