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Smartwatches are a great tool to track your health and fitness on a daily basis. You can use them to monitor your sleep and get notifications from your phone, making them a versatile device for anyone who is interested in keeping an eye on their steps, heart rate, and stress levels. You view that information through the watch's glass, which can be made of sapphire or Gorilla Glass. Both protect the watch but function in different ways.

Sapphire and Gorilla Glass are a type of watch crystal, which is the transparent cover or screen that protects the moving parts underneath — the digital numbers or dials and hands on the clock. Sapphire glass is more scratch resistant but can shatter easier, whereas Gorilla Glass is more robust, sturdier, and lighter, but less scratch resistant. Sapphire is the better option for luxury wear since it doesn't scratch as easily, making Gorilla Glass the better option for workout wear due to its impact strength.

Both sapphire and Gorilla Glass are one reason why no one needs a smartwatch screen protector anymore, as both are built to better protect the watch face. The types of glass used may function the same way but are built rather differently.

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Gorilla Glass is a strong glass developed by the company Corning and durable enough to withstand drops onto concrete. Its strength makes it a good choice for fitness smartwatches with wearers who live a more active lifestyle. If you are a runner, jogger, or workout quite a bit, it's recommended over watches with sapphire glass.

The downside of a smartwatch with Gorilla Glass is it is more likely to show scratches on its screen. Gorilla Glass has been tested on the Mohs hardness scale, a guide used to identify minerals and their strengths, and scored a Mohs hardness of around six to seven, which is roughly middle ground for strength, matching objects like a knife, glass plate, or steel nail.

If you are interested in fitness and want to get a watch that features a Gorilla Glass casing, consider the Pixel Watch, Garmin Forerunner 970, and Xiaomi Watch Color 2. Gorilla Glass watches tend to be less expensive than sapphire, with the Forerunner 970 being $749.99 versus the sapphire glass fēnix 8 – 51 mm at $1,199.99. If you don't want to spend those prices to track fitness, you don't necessarily need a smartwatch anymore.

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Sapphire glass smartwatches are more of a luxury option due to the higher-end material used to build the screen. Sapphire is a durable mineral and one of the hardest ones on the planet, just beneath diamond. This makes the watch crystal more difficult to scratch but does make it easier to break.

When it comes to the Mohs hardness scale, sapphire glass ranked nine out of 10. This is three points higher than Gorilla Glass. Sapphire glass also increases the price of a smartwatch or device. Some users interested in a smartwatch with sapphire glass believe it's not worth upgrading from a Gorilla Glass smartwatch to the more premium mineral.

Choosing your watch crystal glass depends on how often you wear your smartwatch and what you are doing while wearing it. If you work out a lot, then one with Gorilla Glass is going to offer more durability in the event you hit it against a weight or drop it. A smartwatch with sapphire glass is built for showing off your bling. Of course you can always go old-school with traditional watches, but the functionality and durability of today's smartwatches make traditional watches obsolete.