This $150 watch is terrifying for Apple and luxury companies

Watch out, Apple - a cheaper competitor is coming for you.

Sales of the Apple Watch have been disappointing amid criticism that it's uncomfortable, difficult to read, and too complicated to use.

And on top of that, it's really expensive.

The classic version starts at $549. There's the cheaper Sport version which is $349-$399, and the very high priced Edition version which can cost you between $10,000 and $12,000.

This costly product is a tough sell for millennials, who are already strapped for cash.

But now, Slate reports Swatch's Sistem 51 could potentially challenge Apple, as it wins in the price department at a low $150. Slate enthusiastically proclaimed this watch will "change everything."

The 100% Swiss-made watch never runs out of battery and is powered by the body heat of the person wearing it.

This watch earns its status because it's the opposite of the Apple Watch: it's simple, and yet innovative. It's an automatic watch, and it isn't pretentious. Business Insider's Matthew DeBord hailed the watch for "reducing the number of parts in the movement to 51, about half of what a typical automatic watch requires."

The low cost could truly make it more appealing to those who were halting on spending money on big-ticket purchases, like the Apple Watch - or even a fashion watch.

Additionally, watch blogs, such as Hodinkee, have been singing the the Sistem51's praises. When Business Insider got its hands on the blog this past winter, it was hailed as "the coolest $150 watch in the world."

The combination of price, simplicity, and convenience make it an appealing choice for young consumers.

Further, millennials are spending the majority of their money on items such as technology versus apparel and accessories.

Watches could fall somewhere in between tech and apparel, but a YouGov survey found that 60% of 16 to 34-year-olds didn't think watches were necessary in the age of smartphones.

This makes it unlikely they would shell out hundreds of dollars for the Apple Watch.

Additionally, the Apple Watch faces a problem that analog watches do not: battery life.

The Sistem51 runs for 90 hours, which regular mechanical watches last about 40. The Apple Watch, with an 18-hour battery life, requires a nightly charging.

While tech enthusiasts might still find the allure in the Apple Watch, regular consumers might find solace in this watch's simplicity.

And with a reasonable price tag, you won't have to think too hard about shelling out for it.