NASA is adding areal-exploration to its arsenal of Martian rover explorers... Don't know about you, but I'm totally on board with this.
Check out the video below detailing the efforts put forth in this new direction of exploration:
Prototype versions of the Mars Helicopter are being tested now. The idea is proposed as an "'add-on" to future rover missions, so even if it gets approved it won't be flying any time soon. There's a lot of work to be done between now and then anyway. Compared to Earth, Mars has a much thinner atmosphere and much weaker gravity. What's more, the planet's harsh environment means a drone also must be engineered to be rugged enough to withstand Martian conditions while remaining light enough to fly.