Two Methods: QR code and seed phrase
There are two ways you can sync your Ronin Wallet with the mobile app. The first method is to scan a QR code from your Ronin Wallet browser extension.
The second method is by using your seed phrase.
Sync Your Wallet Using QR Code
You can use the QR code generated by your Ronin Wallet to sync it with your mobile app. Before you generate the QR code, please make sure that no one is looking at your screen. If someone has access to the generated QR code, he will have access to your assets. Please see below for detailed steps:
1. Open your Ronin Wallet browser extension then press the 
icon on the top right. Next, click "Settings".
2. Click "Sync with Mobile" and enter your Ronin Wallet password. Before putting your password, make sure that no one else can see your screen. They can use the QR code to steal your assets.
3. A QR code will be generated in your Ronin Wallet extension.
4. Open your mobile app and select Sync with Ronin Wallet Extension then scan the QR code.
5. A confirmation screen will pop-up. Make sure that the information in the Ronin Wallet extension and mobile app match.
6. You will be asked to set and confirm a PIN code.
7. Congratulations! You now have successfully synced your Ronin Wallet to your mobile app.
Note: Please keep in mind that the generated QR code is not permanent and it can expire.Once it was expired then you will need to generate another QR code if you were to need them for scan again.
Sync your wallet using seed phrase
You can use your seed phrase to sync your Ronin Wallet with the mobile app. Please be extremely safe with the seed phrase. These words can be used to steal all your assets. Do not text or electronically send it to yourself. Read it from your written down backup and type it into the phone. Please see below for detailed steps:
1. Open your mobile app and select "Import wallet using seed phrase". You will be instructed to enter your seed phrase. Separate each words with a single space between them.
2. You will be asked to set and confirm a PIN code.
3. Congratulations! You now have successfully synced your Ronin Wallet to your mobile app.