I am using Verizon Motorola Droid Razr XT912 and facing lag issues since i have bought the phone from US. Earlier it was running on ICS but was laggy so i updated to JB 4.1.2 (System version: 98.72.165.XT912.Verizon.en.US). But still i am facing lag issues while recieving calls, exploring launcher etc. I am using "CLEAN MASTER" & it shows RAM usage mostly 80%-90% even i have few apps installed i.e. 78. Where can be the issue? Kindly assist, Thanks!!