If you don't already have the Facebook app on your phone or tablet, you can download it for free from the iPhone and Android app stores, and start using it right away. If you want to see the personal data that the social network has stored instead, you can download your Facebook data to a computer.
Steps
Method 1 of 2: Download Facebook to iPhone

Step 1. Open the App Store on your iPhone

Tap the App Store icon that looks like a white "A" on a light blue background.

Step 2. Tap Search
This is the tab at the bottom right of the App Store screen.

Step 3. Select the App Store text field
This text field is at the top of the screen. Tap on it to bring up your iPhone keyboard.

Step 4. Search for Facebook
Type facebook, then press To research at the bottom right of the keyboard.

Step 5. Tap GET
This option is to the right of the Facebook logo.
- If you've downloaded Facebook before, you'll need to tap the cloud icon instead

Step 6. Enter your fingerprint or password
To start the installation of Facebook on your phone, you can either use your fingerprint or type in your Apple ID password.
- IPhone X users can simply look at their screen to use the facial recognition feature.
- You can open Facebook as soon as the installation is complete by pressing TO OPEN in the App Store (or by tapping the Facebook app icon on any of the home screens).
Method 2 of 2: Download Facebook on Android

Step 1. Open your Android's Play Store

Tap the Play Store app icon that looks like a multicolored triangle on a white background.

Step 2. Tap the search bar
The search bar is at the top of the Play Store page. Tap on it to bring up your Android keyboard.

Step 3. Search for Facebook
Type facebook in the search bar. A drop-down menu with the corresponding search results will appear.

Step 4. Select Facebook
Facebook is in the drop-down menu and opens the Facebook application page.

Step 5. Tap INSTALL
This button is at the top of the page.

Step 6. Choose ACCEPT
The Facebook app will be installed on your Android.
- Once the Facebook application is installed, you can immediately open it by pressing TO OPEN in the Play Store (or by tapping the Facebook app icon in the app drawer).