1. An aimer accessory for a mobile device, the aimer accessory comprising: a body configured for being affixed to the mobile device, the body comprising a collimator terminating with a grating disposed in a distal portion thereof, the grating configured to receive light from a lamp of the mobile device, and to generate a light pattern on the surface containing a barcode; wherein registration of the light pattern and the barcode in a scan area enhances the ability of the mobile device to capture a barcode image.