Beem-enabled cinema advertisements or APG|SGA billboards emit a high-frequency sound outside our hearing range; billboards also emit a Bluetooth signal. These signals are received from the Beem platform; because it is integrated with many popular apps, there is no need for the user to download a special app. Beem is currently integrated with the 20 Minutes, Watson and Bluewin apps. If a user has one of these apps open, they will see an unobtrusive notification as soon as the signal is received. Selecting this notification opens the Beem platform, where the user will be shown additional, updated information or offers relating to the billboard, programme or commercial. This may be purely informative or might include competitions or votes that the user can take part in, as well as special offers and vouchers.