Windows Mobile was Microsoft's operating system for touchscreen phones and Pocket PC devices in the 2000s, and version 6.x powered many business and early smartphones before modern app-based phones took over. Its system sounds, including the file labelled Attention, were short functional alerts designed to be heard over calls and music. Long after the platform faded, the low battery chime survived on soundboards, where it is shared by former users and retro technology fans who recognise it instantly as the sound of an ageing phone giving up.