The smartphone segment includes smartphones with Safari 10+, Chrome 49+, Firefox 49+ or Edge 13. It is advanced browsers but with limited screen sizes and processing power, compared to desktop computers.
Smartphones are defined by a display size smaller than 6". However this is more of a guideline, than a strict rule. There are some phones out there, that are more than 6" but where resolution, performance or even assumed user expectation, clearly makes them a phone. Those devices are still indexed as phones, despite their large screen.
As of December 2017 this segment represents ~81% of the mobile browsers and ~37% of all browsers (across all device types).
The smartphone segment is defined by the following criteria:
- Primary input method is touchscreen
- Browser supports the smartphone segment requirements
- Screen width of minimum 320 pixels in portrait mode
- Screen is 3.5 to 6 inches
The smartphone segment supports the following features:
- Web audio
- ES6 Classes
- CSS Transforms
- CSS Transitions
- CSS 3D Transforms
- FileReader API
- File API
- CSS Animations
- Offline storage
Check out the complete feature support on caniuse.com.