How to set a passcode lock?
To set a passcode lock
1. Open the Bigin app on your iPad.
2. Tap on Settings 
at the bottom right of the screen.
Under "Manage Privacy", you can find the title "Privacy & Security".
3. Tap on Privacy & Security > Passcode Lock.
4. Select "Turn Passocode On".
5. Set a passcode.
Info: Once you've set a passcode, the next time you tap on the Bigin app icon to open the app, you'll need to use the passcode to enter the app.