You can see the private key with the following steps:
1. Tap the icon at the top right of the home screen
2. Tap “Privacy & Security”
3. Tap “Advanced Settings”
4. Tap “Show Private Key”
5. Tap “I got it”
6. Enter the passcode
7. Choose the currency of which you want to see the private key
8. See the private key displayed here
The private key is the important part that proves ownership of your cryptocurrency assets. Please be very careful handling the private key to prevent it from being used by others.
See the link below for more details about private key.