Developed and created by Philip Frenzel, a student from Aalen University in Germany, the AD Case functions essentially as an airbag for a smartphone to protect it from possibly destructive drops. The term "airbag" does not quite do the case justice, as the smartphone saver doesn't use an inflatable cushion and instead employs built-in sensors and eight hook-like springs that deploy when the phone senses it is in free fall.
The springs employed in the AD Case allow the phone to bounce harmlessly after they deploy, ensuring that a phone does not take any damage after coming to a rest. From there, the springs can be easily folded back into the case, and are once again prepared for another drop. The design and construction of the AD Case won Frenzel the top award from the German Society for Mechatronics and has been registered as an official patent.