thanks for the response.
you say its in a case, have you tried taking the phone OUT of the case and just used it that way to make calls? just to rule out any foul play from the case.
what case do you use by the way?
all one can do online without seeing the device is try and offer opinions based on what is posted, and with the other threads on this page that have issues, its hard to diagnose properly.
i would say take it out of the case and see if it makes a difference.
one other thought, is this offense repeatable? meaning, can you do certain steps to make it lock up/become unresponsive every time?
if so, i would take it into a sprint store and have them smoke it over. show them the issue and see what they say.
the only thing left to do is a factory reset. if you have had the phone over a year and have not ever factory reset it, now may be a good time to do so. you will get all of your apps back and your contacts if you have synced them up on google.
let me ask this: do you use any live wallpapers?
do you minimize apps (instead of using the back arrow to back out of an app, you just use the home button)
or do you close out apps (use the back arrow button to close them out -- doing this will close the app)
those questions are just curious questions...
99.6% of the time a factory reset will cure nearly any issues...