The Dry Earth Trilogy

The invaders came down to Earth in their ships and multi-legged battle armor, and we had no way to stop them from taking the water. Made sense. They looked like massive crabs, after all. The war was over in days. Now, those left behind eke out a parched existence in the scorched rubble, avoiding the hunter-killer teams of crabs as they scour Earth for whatever they deem valuable. 

Sixteen-year-old Yasmine Whitten is an expert at navigating the wastes; born into this world, she not only survives; she thrives. But she's got a secret: her mother's old cell phone. 

Kept intact for 13 years of alien invasion and kept charged by a tiny solar panel, these two relics of a dead world give her sanity and a host of tools that allow her to stay ahead of the scavengers, both human and crab alike. It's a flashlight and a camera, and when she can't sleep, she can comfort herself in the cold desert by looking at pictures of her mother and father and by reading their old text messages to one another. She's doing well enough, for a teenager on her own in a ravaged world. Until the phone rings.   

The Phone is author W.J. Orion's first young-adult science-fiction novel. First in a planned trilogy of Dry Earth titles, it's suitable for teenagers and adults alike.