The active dampening (AD) phone case, patented by German student Philip Frenzel, is a slim alternative to bulky phone cases, but comes with a nifty trick.

So far it's only a prototype — but the AD case can detect when the phone is falling and protract springs to make the phone bounce when it hits the ground, which should prevent any scratches or cracks on flat surfaces.

Once you pick the phone back up, you just fold the springs back in.

There are plenty of case options to effectively protect mobile phones from damage — whether it's water damage, cracks, scrapes or anything in between. But these cases often come with a price: They add significant bulk to devices that are typically carried around in pockets all day.

A German student named Philip Frenzel has patented a potential solution for this problem: the AD (active dampening) phone case. The case comes with sensors that can detect when the phone is in free-fall, which prompts the release of four springs that cause the phone to bounce when it hits the ground — dampening the impact, and hopefully preventing any scrapes or cracks.

While the case seems like a good solution for drops on flat surfaces, it doesn't look like it would prevent scratches or cracks if the phone fell onto a jagged edge or anything that is uneven.

It's not for sale yet, but Frenzel has already acquired a patent and has received an award from the German Society of Mechatronics for his creation.

Here's a video showing how the case works: