What do smart glasses do?

Smartglasses or smart glasses are eye or head-worn wearable computers.  Many smartglasses include displays that add information alongside or to what the wearer sees.  Alternatively, smartglasses are sometimes defined as glasses that are able to change their optical properties, such as smart sunglasses that are programmed to change tint by electronic means.[4]  Alternatively, smartglasses are sometimes defined as glasses that include headphone functionality.

A pair of smartglasses can be considered an augmented reality device if it performs pose tracking.

Superimposing information onto a field of view is achieved through an optical head-mounted display (OHMD) or embedded wireless glasses with transparent heads-up display (HUD) or augmented reality (AR) overlay.  These systems have the capability to reflect projected digital images as well as allowing the user to see through it or see better with it.  While early models can perform basic tasks, such as serving as a front end display for a remote system, as in the case of smartglasses utilizing cellular technology or Wi-Fi, modern smart glasses are effectively wearable computers which can run self-contained mobile apps.  Some are handsfree and can communicate with the Internet via natural language voice commands, while others use touch buttons.

Like other computers, smartglasses may collect information from internal or external sensors.  It may control or retrieve data from other instruments or computers.  In most cases, it supports wireless technologies like Bluetooth, Wi-Fi, and GPS.  A small number of models run a mobile operating system and function as portable media players to send audio and video files to the user via a Bluetooth or WiFi headset. [10][11] Some smartglasses models also feature full lifelogging and activity tracker capability.

Smartglasses devices may also have features found on a smartphone. [16][17] Some have activity tracker functionality features (also known as "fitness tracker") as seen in some GPS watches.

As with other lifelogging and activity tracking devices, the GPS tracking unit and digital camera of some smartglasses can be used to record historical data.  For example, after the completion of a workout, data can be uploaded into a computer or online to create a log of exercise activities for analysis.  Some smart watches can serve as full GPS navigation devices, displaying maps and current coordinates.  Users can "mark" their current location and then edit the entry's name and coordinates, which enables navigation to those new coordinates.

Although some smartglasses models manufactured in the 21st century are completely functional as standalone products, most manufacturers recommend or even require that consumers purchase mobile phone handsets that run the same operating system so that the two devices can be synchronized for additional and enhanced functionality.  The smartglasses can work as an extension, for head-up display (HUD) or remote control of the phone and alert the user to communication data such as calls, SMS messages, emails, and calendar invites.