Hello,
I have gone through your requirements, you want a app that track every incoming SMS and if specific keyword found in it vibrate phone or produce alarm sound, So Yes I can complete it in few hours. I am very aware with background task and SMS reading functionality so its easy for me to do this task for you.
I am fresher on this platform But I have worked on more than 25 android applications in four and half years of my professional career.
I am full time freelancer so always available for support and communication.
Let me know if you are interested, I can start working on it right now.
Thanks,
Hardip