It's getting quite difficult to differentiate one smartphone from another, and that will become increasingly the case as bezels disappear. So there's going to be more emphasis on new and unusual features being added to handsets. For Samsung, one of those features looks likely to be a breathalyzer.

The Korea Times reports that Samsung Electronics filed a patent for a new invention involving the S Pen stylus. The patent was actually filed with the US Patent and Trademark Office back in June 2016 and awarded to Samsung last month.

A Samsung official has since revealed that the patent is for an S Pen that is capable of measuring a user's blood alcohol content. It does this by bending a small section of the S Pen 90 degrees to reveal sensors which measures blood alcohol from the breath passing over it. The reading is taken while the phone is in use and the user is talking. The same S Pen rotation may also be used to reveal a microphone.

The S Pen ships with Samsung's Galaxy Note smartphones, with the Galaxy Note 8 preparing to launch on August 23. However, it seems unlikely the breathalyzer feature will be included with the Note 8's S Pen. Instead, we should expect it in next year's Galaxy Note 9.

Adding a breathalyzer to smartphones makes sense as it's the device we all carry around and regularly place within close proximity to our mouth. If the breathalyzer test is carried out automatically whenever we talk on the phone, an alert could be brought up on the handset when the blood alcohol level is too high to drive, for example. Invoking the test manually should also be possible so a user can check their own state before deciding how to get home.

Whether the breathalyzer makes it into a smartphone depends on how reliable the sensor is and how accurate Samsung can make it. If it does ship with the Note 9, I'm sure it won't take very long for a Note-owning drunk driver to claim "my phone told me I was fine" as their defense in court.