Vsmart phones were sold by Vietnam's VinSmart from the late 2010s into the early 2020s, and their system alerts have outlived the handsets themselves online. This low battery tone later circulated as part of mobile device charging sound compilations, where short notification clips are collected for editors. Like a simple ding sound effect, it survives because it is instantly readable across languages, no voice or explanation needed. Creators keep reusing it for phone, battery and running-out-of-power gags even for viewers who never owned a Vsmart device.