I have a Nexus 4, and noticed when I power off (press power button, tap power off from the menu) and turn phone on or reboot (hold down power button for 10 seconds and wait for phone) that apps I had opened are still open when the phone turns back on (maybe to be more precise, they are still in the recent apps history and open to the same place they were when I closed them)

Does anyone know if this is by design?
I've tried to search but have failed