I tired so many times to install it because it really help to customize our phones right? Then why samsung did not release it for all phones? They released for some of the mobiles which are new mobiles! Your old customers also want to use it then after they prefer you if anyone asked about samsung phone to buy. Release app lock for all kinds of samsung mobiles. Please! Not only me, there are so many persons could not use the app lock they regret about it. So, please! Release it as soon as much. We are waiting to use it and to explore it. Samsung.