Es File explorer is a good app for mobile. If you have this app so you can do anything like connect with other phone with lan , ftp , cloud , remote manager and manyways. You can lock many things by the password with the help of this app noone manager or explorer can unlock that thing. You can unlock only from this app. If you have any zip file so you can extract zip file from this app.You will get a lot of features in this only obe app and you can run this app very easily. You do not need any helper or any book to run this app.