If you've ever used an iPhone or a recent OnePlus device, you've undoubtedly encountered the switch on the lefthand side above the volume buttons. While the exact functions of the switch will depend on which company's phone you're using, the main idea is the same: a hardware switch that instantly mutes your phone, without having to turn on your screen and adjust the volume manually.

Few would call this switch a necessity, but it's convenient all the same.

It sounds a bit lazy, sure, but in practice, this switch can be a lifesaver. If you're in the middle of a meeting, job interview, or movie, you can't (or at the very least, shouldn't) pull out your phone at any point, but an unexpected phone call can cause an embarrassing scene if you forgot to silence your phone beforehand. With the volume switch, you can put your phone into Silent or Do Not Disturb mode right from your pocket, without alerting anyone around you.

Particularly in the case of OnePlus, this switch is also useful for quickly switching between different audio profiles. Rather than a simple on/off switch like on the iPhone, phones like the OnePlus 5T use a three-spot slider that switches between the Silent, Do Not Disturb, and Ring profiles, all of which are configurable in the phone's settings. You can set different volume levels for media across different profiles to quickly switch between, or leave media volume completely off in Silent mode to quickly mute video ads and games you don't want to hear.