Recommended App For Change of Vibration Intensity

[AC Question]

I have a Blu Studio 5.0 II with stock Android 4.2.2 (Jelly Bean).
I would like to control the intensity of phone vibrations when receiving a call or SMS.
What (free) app do you recommend?

Please notice that I have a _stock_ Android 4.2.2, so there is no Sound entry in my Settings screen that allows me to control the vibrations intensity.