Net Deck does not collect or store any personal data whatsoever.
If you're adding your NetrunnnerDB.com or Jinteki.net account data to Net Deck, the usernames and passwords are securely saved in the keychain on your device, and are only used to log in at those sites via https.
Net Deck uses anonymous usage and crash reporting from Fabric. Read Fabric's Data Processing and Security Terms for more information.