Change the App Assigned to the Convenience Key - BlackBerry®
From the Home screen All tray, select Options. To expand the tray, press the Menu button then select Open Tray.
Select Convenience Keys.
Select the current setting from the right side / left side convenience key opens field. If preferred and applicable, repeat this step to configure both Convenience Key Opens options. Depending upon model, there may only be one Convenience Key Opens option.
Select the one of the following applications (e.g. Calculator).