theres an app called Bluff My Call which spoofs the caller id of the person you are calling.I only use the free version which allows me to spoof the caller id # to anyone i call so they can think im calling from a different phone #.The free version only allows 2 minute phone calls and then it just hangs up or it also allows u to send a msg directly to their voicemail with the fake caller id #.but if u pay for the app it also has the options to alter ur voice so that a man sounds like a women and a women can sound like a man,and u can also record the calls if u pay for the app.but i dont even know how much the app costs bcuz all i like to use is the caller id spoofer,and 2 minutes is enuf time for me to say what i need.But i know that app has a voice disguiser.ive never used it tho bcuz ive never bought the app.but it could be worth looking into.or just download and install the Bluff My Call cab and take a look at it and see if its something u might even be interested in.Its definetly a fun app to play with people tho.Let them think u get a new # every day,or mess with some mean ex-girlfriend and mayb call her new boyfriend when hes at work and let him think that you are calling from her phone,or whatever else u can think of.Harmless fun....