aptX (HD) over Bluetooth (many Android compatible headphones), requires media-plugins/gst-plugins-openaptx.

Packages describing “aptx” as local USE flag

Package “aptx” Flag Description
media-sound/pulseaudio-daemon aptX (HD) over Bluetooth (many Android compatible headphones), requires media-plugins/gst-plugins-openaptx.
media-sound/bluez-alsa aptX (HD) over Bluetooth (many Android compatible headphones)

All packages providing a “aptx” USE flag (2)