The phrase "alarm feature" refers to a function or capability of a device that can be set to make a loud noise or sound at a particular time as a reminder or to wake someone up. Full definition
There is also a silent alarm feature, which is nice if you need to wake up earlier than your partner. (heavy.com)
It has five sensitivity settings for different water conditions and a fish alarm feature. (geekwrapped.com)
You can start and stop a Spotify playlist with Flash, or you or connect Misfit's sleep tracking and smart alarm features with the Nest Learning Thermostat to wake up to an ideal temperature. (pocket-lint.com)