The ContactMasterKit app is a contacts backup utility that allows you to import contacts and emails from one device to another. This import is possible in two different ways: through the Internet and via a local connection (via cable, Wi-Fi, or other types of connection). Importing contacts through the Internet is more secure, as it prevents any unauthorized access to your device. It also ensures that you don't have to enter any passwords or other confidential information. The second way is through a local connection. With this method, you can connect to your device via a cable, Wi-Fi, or other type of connection. You will need to enter the contacts that you want to backup and the app will export them in a vCard or CSV format.