When you get a new Mi phone and want to keep all your data such as contacts and messages, you can use Mi Mover to do it. The app by Xiaomi can transfer all files from both Android or iOS.
The process of migrating data between Android devices is the same as when you do it with Mi Mover. Once you've fired up the Mi Phone, start the app as a recipient. The old phone should be on standby and the same WiFi as the new Mi device. You can speed up this process by connecting both to the same hotspot.
It consumes a minimal amount of mobile data to get all your files copied. You can select which type of files you want. They include contacts, messages, applications, and WiFi passwords. After that, it would take a few more minutes for the Mi Phone to finalise the new setup.
One of the worst things about Mi Mover is how difficult it is to remove it. Most Android users, if not all, have a Google account where they back up all their files. Regular Android devices can also transfer data without a third-party app. That renders Mi Mover almost useless.
This app gives itself invasive permissions to your phone, including storage, and disabling it isn't an option. To remove bloatware apps such as this one, rooting the device is the best method. If you don't have the knowledge or the time, try disabling it through the hidden Mi settings or Android Debug.
As fast as Mi Mover can extract data, it doesn't receive all of what you send. It may take several runs to transfer 100% of the files you need. The app doesn't always take all your messages or call history.
Overall, considering how much effort it takes to do one simple task, this app seems like a bit of a waste of time. On top of that, the fact that Xiaomi doesn't give you the option of removing it should raise concerns for all users. Mi Drop does the same thing without the need to download an apk, but it belongs to the same company, so isn't a much better choice.