Yellow Jacket is an iPhone case with a stun gun inside.
Flip down a hinged cover to reveal two small metal prongs. Slide the safety switch and a press of a button will deliver 650 volts to an attacker. The stun function is powered by a separate battery (not your phone’s) which makes the case heavy, but the extra peace of mind in a dark parking lot may be worth it.
More information is available at www.yellowjacketcase.com/