Universal security apparatus for wearable electronic devices

An anti-theft device for securing a wearable electronic against unauthorized removal from a display counter. The anti-theft device has a stand configured to be attached to a display surface. A shelf configured to support the wearable electronic is affixed to the stand. The shelf of the anti-theft device has a recess configured to receive interchangeable inserts. Each insert has a first surface sized for insertion into the recess and a second surface configured to couple to a charger. Each insert also has a notch, which is configured to be at least partially aligned with an aperture of the recess. A charger is coupled to the insert, and an electrical cable connected to the charger is routed through the notch and the aperture. The charger supplies power to the wearable electronic when it is positioned on the shelf of the anti-theft device.