Communication with people through smartphones has brought us many benefits and convenience. Working with each phone number is complicated, but with the arrival of support apps, that’s no longer a problem. Also, Google Play has appeared countless support applications to help users to organize their contacts neater and more comfortable. However, their features can only be limited to contacts, and they no longer have many attractive features. But with 2ndLine, everything will be different, because it is a completely new support application with many diverse and great features. It is not only limited to a certain area, but it can do many other things to make it more comfortable for users to use the phone.The essence of the application is the ability to organize contacts and help users manipulate easily with incoming or outgoing calls. And to give users the best experience, they have to start with the interface. The interface of the application is designed to be simple, similar to a phonebook, but more versatile. The app uses simple colors to create a user-friendly interface. The exciting thing is that the interface will work flexibly; it will constantly change based on user actions. Even with a simple operation, users can access new categories of applications. Of course, user settings also allow users to customize the interface based on the style of use of each person.The ability to manage contacts of the application is evaluated very well by the user community, and it allows users to know the information of the callers. While that is basic in most phonebook applications, it is more detailed than ever. The interesting thing is that even if a stranger calls, the application will access the information of the other party, from which it automatically displays the name of the incoming caller. Not only is its ability to be unlimited, but it can also allow users to use other applications during a call. The noise-canceling feature of the application will also be added, from which the user’s voice will become clearer and more transparent. User contacts can also be customized freely, whether it’s a contact or interface settings. The app has everything a user needs to have a better experience with their contacts.2ndLine is free, all its features are completely free and endless for users to use it for a long time. However, the most outstanding feature of the application is impersonating the phone number of the user. Impersonating phone numbers allows users to do many things. Like using it for sign up processes, or contacting multiple blocked phone numbers. But users can still receive incoming calls through their original phone number. The app has various options for users to forge phone numbers, like numbers and even area codes.The application not only supports users in making calls or managing contacts, but it also supports users with a perfect messaging tool. The messaging feature allows users to attach files, voice calls, or other things. 2ndLine is undoubtedly one of the best apps that everyone’s device must have to experience a sense of convenience and usefulness.