Snoop — Gordon Korman

From Gordon Korman, the bestselling author of Restart, the story of a boy who's stuck at home with two broken legs... and who starts using cameras and a drone to spy on his classmates, neighbors, and a possible criminal who's come to town.
If Carter hadn't been checking his phone, he might have seen his brother coming down the ski slopes in his direction. And if Carter had seen his brother in time and avoided the crash, he might not have two broken legs right now.

Oops.

Now Carter is stuck at home for weeks, with both his legs in casts. Bored, he starts checking out the live feeds from police cams around his town. Before he knows it, he's obsessed -- watching his classmates when they don't know he's looking, and discovering some other VERY STRANGE things going on that no one else is noticing.

But what happens when Carter is found out... and the people he's watching know where he lives?