Features
• encryption AES-256
• attachments (will encrypted if enabled encryption for note)
• view and edit attached files inside application (text and html, photo)
• folders: unlimited nesting (only in full version)
• formatting text
• password's input methods ( digital/full/pattern 3x3/pattern 4x4)
• quick login (short password/fingerprint scanner/biometric)
• clearing data after many attempt to wrong password
• separate password for imperceptible data clearing
• auto-lock by time
• widgets and shortcuts for notes or attached files
• icon library (custom icons)
• color themes
• backup/restore database
• reminders
• labels
• support "Samsung DEX"
• does not contain advertising
• does not require Internet access

Some explanation:
• encryption is disabled by default!
• data will be encrypted using you password
• note encryption is enabling in the note editing window.
• the note body and attached files will be encrypted, the note name is not encrypted!
• attached files are encrypted if encryption is enabled for the note they are attached to

VirusTotal: https://www.virustotal.com/gui/file/aaac7aa6411da339a61bd2c1f19199d919a217c95700b1b50aa5d5f7053d8755