To Take complete backup, check the following steps :-
1.Go to Settings, Personal, Backup and reset, and select both Backup my data and Automatic restore.
2.Go to Settings, Personal, Accounts & Sync, and select your Google account.
3.Select all of the option boxes listed, to ensure that all available data is synced.
To check all the other details of the device use, this link: Vivo X21
To Transfer files from your phone to another device.
1. To transfer data from your phone to a Laptop
Use the data cable that came along with your phone. Simply plug in your device and start transferring your data to your laptop.
2. To transfer data from a phone to phone.
There are many ways you can transfer your data like Using the Shareit app(https://play.google.com/store/apps/details?id=com.lenovo.anyshare.gps&hl=en), Bluetooth etc.
Using shareit app: Just download the shareit app on both the phones and open it.then select the app, photo, video you want to transfer from the list and press "Send". It will search for the nearby device. Once the device appears tap on that your file will be transferred.
You can check the complete specs of this phone
To cast your phone screen on your TV you need to have Chromecast.Follow the steps to successfully cast your screen-
Before you begin casting
1. Connect your phone to a Wi-Fi network.
2. The mobile device, tablet or computer you are using to cast must be on the same Wi-Fi network as your Chromecast .
3. You must be running the latest version of the Chromecast-enabled app. You can always double check that you are on the latest version by visiting the Google Play Store.
Cast from Chromecast-enabled apps to your TV
1. Make sure that the phone you are using to cast is on the same Wi-Fi network as your Chromecast or TV with Chromecast built-in.
Open a Chromecast-enabled app.
2. Tap the Cast button Inactive cast extension. Note: The Cast button isn't located in the same place on all Chromecast-enabled apps.
3. Tap the device you'd like to cast to.
4. When you're connected, the Cast button will turn color, letting you know you're connected.
5. Select the app like Youtube, Broswer,Google Music etc
You can now cast videos, movies and TV shows directly to your TV.
To stop casting, tap the Cast button and then Disconnect.
You can also watch this step-by -step guide to do the same
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