To ensure data is stored securely on your iPad, you should set up a passcode.
Setting a passcode will enable encryption on the data that is temporarily stored on the device while collecting offline.
How to Set Up a Passcode
1. Launch the Settings app.
2. Tap Passcode.
3. Tap Turn Passcode On.
4. Set a passcode.
Your iPad now requires a passcode when it is turned on, and all data is secure.