When will book 4 come out?

I just finished book three a few days ago and i really didn't like the ending. i came to this site hoping that i would find out when and if a 4th book was coming out. Does anybody know? it's driving me insane!

I Know Right...

Your not the only one...

Catch you on the flip side!
Fixer Krystal Meyers, #52
The World
Sector 122
Live to fix, fix to live

P.S. Don't call me Krystal, call me Krys.