Daily Notes Planner (iOS and MacOS):
All notes in Daily Notes Planner are stored securely in users' local devices so only users themselves can access them. No other apps or developers, including the creator, Inho Hwang, can access users' notes. Daily Notes Planner apps do NOT use internet except for when users are syncing their notes to their own personal iCloud account. Users can save their notes in their own personal iCloud server in order to sync the notes to other devices logged into the same iCloud account. The developer, Inho Hwang, has no access to users' notes whatsoever, and he does NOT have any personal server set up anywhere in the world and has no intension to do so for any other means as of today's date of October 7th 2018. Users' notes are fully theirs, and the developer keep their notes safe by best following Apple's guidelines and implementing latest technology such as Sandbox feature, Core Data, and iCloud. The developer fully understands that violating user's privacy will directly result in removal of apps from the App Store and termination of the developer's account.
S Pen Planner (Android):
All notes are saved locally inside internal storage. Notes cannot be backed up elsewhere and are stored locally inside the device so that users themselves can access them.