"Laser jack" is a earphone port-mounted laser pointer for your iPhone, iPod touch, or iPad. The “Laser jack” App can power on or off the laser beam via the iphone earphone port without external battery. By use of two big sliders in the APP, user can adjust the laser beam intensity as well as set the laser to flash at rate from 4.0hz to 0.5hz smoothly. The perfect user friendly operation makes the product “Laser jack” works smoothly.
You can see the demo on youtube