The phrase "alert slider" refers to a physical button on a device, usually a smartphone, that allows you to quickly switch between different alert modes like silent, vibrate, or loud.
Sentences with «alert slider»
That means the textured alert slider on the left, above the volume switch, and the power button on the right. (pocket-lint.com)
On the side, the notification alert slider makes a welcome return. (digitaltrends.com)
On the side of the body, the notification alert slider makes a welcome return. (digitaltrends.com)