how to create a funny voices(clinton voices) like battery watch?


hei guys i want to develop android app that has a funny voice like donald duck etc because im inspire from battery watch whic is android app that has funny voice like sticth and clinton and i want to ask you a question to create a funny voices like battery watch? and how to put our funny voices to android app
2.what software that produce a funny voices like clinton and sticth etc that battery watch use it to develop their app to create obama voices just like battery watch develop a funny voice for alert for battery
i hope you guys reply,because its urgent for me thanks
(because i want to develop alarm clock for android
) i hope you guys help me thanks

this is their app
appbrain dot com/app/battery-watch-%E2%98%85%E2%98%85%E2%98%85-funny-voices/com.s4bb.batterywatch
play dot google dot com/store/apps/details?id=com.s4bb.batterywatch

just change dot with .