Is the Apple Watch secretly waterproof?

The Apple Watch is water-resistant and Apple CEO Tim Cook even says he showers with his on. But can you actually take it for a swim without destroying its complex circuitry? The answer isn't so clear.

A number of video tests suggest the Apple Watch is more water-resistant than Apple is letting on.
The Apple Watch has a water resistance rating of "IPX7 under IEC standard 60529," which means it can be submerged in 3.3 feet of water for up to 30 minutes. 
One such test conducted by Consumer Reports, an independent nonprofit that tests products to the strictest standards, found the Apple Watch Sport and Apple Watch (stainless steel model) worked after being submerged for 30 minutes in a tank of water.

In the video, they take an Apple Watch Sport into the shower and lather it up with shampoo and hot water. It still worked. 

After submerging it in a bucket for five minutes, they decided to take it for a swim. In a 3.9-foot deep pool, the Apple Watch Sport continued to work while submerged for 15 minutes, although its touchscreen was unresponsive; the digital crown, however, worked perfectly underwater.

So yes, the Apple Watch is water-resistant and you can probably take it into the pool for no more than 30 minutes, but Apple still recommends you don't.

Exposure to liquid Apple Watch is water resistant but not waterproof. You may, for example, wear and use Apple Watch during exercise (exposure to sweat is OK), in the rain, and while washing your hands. If water splashes on to the watch, wipe it of with a nonabrasive, lint-free cloth...
• Soap, detergent, acids or acidic foods, and any liquids other than fresh water, such as salt water, soapy water, pool water, perfume, insect repellent, lotions, sunscreen, oil, adhesive remover, hair dye, or solvents.
Submerging Apple Watch is not recommended. Apple Watch has a water resistance rating of IPX7 under IEC standard 60529. The leather bands are not water resistant. Water resistance is not a permanent condition and Apple Watch cannot be rechecked or resealed for water resistance.
The following may affect the water resistance of Apple Watch and should be avoided:
• Dropping Apple Watch or subjecting it to other impacts.
• Submerging Apple Watch in water for long periods of time.
• Swimming or bathing with Apple Watch.
• Exposing Apple Watch to pressurized water or high velocity water, for example, showering,
water skiing, wake boarding, surfing, jet skiing, and so on.
• Wearing Apple Watch in the sauna or steam room.
The Apple Watch's water-resistance rating is on par with what you'd get from fitness trackers like the Jawbone Up. According to Jawbone's Up FAQ, the tracker is "rain, splash, sweat, and shower-resistant, but you should remove your band before swimming, surfing, or exposing to other extreme conditions and activities like saunas and steam rooms." The company further advises users to "not submerge your band in liquids, including hot tubs or baths, at any time."
There you have it. Swim and shower with the Apple Watch at your own risk.