Before revision:  The handset model plays a decisive role in CPU requirements of the application. t-tests showed that IMO has a statistical better performance that WhatsApp whatever be the Android at a significance level 1\%, on Galaxy Note 4.
After revision:  The handset model plays a decisive role in CPU usage of the application. t-tests showed that IMO has a statistical better performance that WhatsApp whatever be the Android at a significance level 1\%, on Galaxy Note 4.