  By monitoring changes in your conversations, your phone will
soon know if you’re happy, stressed, or sad, and can nudge you
toward feeling better.  At moments of high stress, the less
self-controlled among us might come close to throwing their cell
phone against the wall. But soon, your phone might help you
relieve some of that stress (or at least better mange it). An
app on your smartphone could soon tell you when you’re stressed,
or worried, or suffering from a more serious mental health
problem.  Devices like Nike+ or Jawbone’s UP bracelet keep a
daily, constant record of physical fitness, but the system that
Tanzeem Choudhury, a computational wizard at Cornell University,
designed reaches out a step beyond physical fitness to the
comparatively untracked terrain of mental health.  Choudhury’s
sensing system uses machinery in a smartphone—mainly the
accelerometer and the microphone—to monitor people’s movements
and speech, respectively. Collaborating with Andrew Campbell at
Dartmouth, she’s created algori