What's the One Vacation Gadget You Can't Live Without?

It's Monday morning in late July, and if you're not on vacation, you'd almost certainly rather be. So rather than checking email or filing a report, let's think of sandy white beaches and the one gadgets you never leave behind. Whether it's a Kindle for your beach read or some portable speakers for your campsite, we all have a go-to device we never forget to pack. So what's the gadget you never leave at home when you're vacationing?

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