They may be the most mind-blowing invention ever. But are smartphones as amazing as we think they are?

They have never: Cooked a delicious meal; hoisted the sails; shoveled snow.

What’s more, they can be troublemakers, as an ever-growing body of research and press suggests…

• Smartphones can ruin vacations.

Our regal friends at Princess Cruises did some research and found that 67% of Americans would feel completely relaxed if they were entirely “off the grid.” 52% said that having a smartphone “makes it harder to relax.” Yet a cruise without wifi would be like a cruise without booze.

• Smartphones screw up your love life.

NYT and a boatload of researchers report that devices (not the bedroom kind) are making partners feel ignored, insecure, disconnected, abandoned, and just plain bummed. What happens when the shunned partner finally says, “You don’t turn me on anymore?”

• Smartphones cause “tech neck.”

Fact: Bodies age. Fact: Smartphones speed up that pain in the neck. Way back in 2011, 83% of cell phone users reported some neck and hand pain from texting. More recently, a local chiropractor says 80% of her cases are likely be related to phones. Not familiar with tech neck? Take a selfie next time you’re staring at your smartphone.

• Smartphones make kids slow and fat.

I’ve been sitting on this research for a while, but that keeps me in the theme. In short, the WHO believes that 80% of kids worldwide are not getting enough exercise. It takes youth (9-17), on average, 90 seconds longer to run a mile than it took their parents. There’s plenty of blame (and munchies?) to go around. But techno devices increasingly keep butts stuck in seats.

• Smartphones kill conversations. 

What’s better than sitting around chewing the fat with friends and fam? Checking your smartphone, apparently. Thus deteriorates thousands of years of progress in communicating via body language, expressions, and eye contact (remember that?). Run your own test: Ask some gathering, “Which ________ song said ______” See how many phones flip out. See how many memories die.

Not to worry. I got me an iPhone 6 now. The whole wide world is at my fingertips, right?

LOL.