Blackberry bold 9780 problem?

my blackberry bold 9780 has low battery life,I need to charge it everything,whereas my friend who has the same phone says his phones battery lasts for 2 - 3 days,I has this app of an hip hop radio station,I uninstalled it,the brightness in low,vibrate is off,I charged it in the morning now 85% is left,is it normal ?