As per the operating system limit we can’t install same app 2 times in any phone. In this context Sridhar Nallamothu, Editor, Computer Era magazine, explains about one legal method for multiple app installations like 2 whatsapp, 2 facebook, 2 twitter etc in same mobile.
http://computerera.co.in
http://youtube.com/nallamothu
http://nallamothusridhar.com