Open a private AI journal that never leaves your phone. On-device AI gives every entry a real reflection, tracks emotions and patterns, and learns you over time.
CortexOS is the journal that learns who you are.
Write or speak. CortexOS listens, understands your emotions, and gives you something no other journal can. Everything runs on your device. No cloud. No data harvesting. No one reads your words. Ever. EU AI Act compliant.
NEW: PULSE
Tap a mood, write a sentence, save. A 10-second check-in for busy days. Counts in every mood trend, never uses up your monthly free entries.
YOUR AI GETS SMARTER OVER TIME
Most journaling apps treat every entry like the first. CortexOS builds a private understanding of your patterns and growth. We call it Adaptive Intelligence.
NEW: VENT & BURN
A space for the heavy stuff. Speak or type. Nothing is saved unless you choose to keep it. Audio is securely wiped after transcription. When you're done, the entry burns. Nothing left, on your phone or anywhere else.
DEEP ANALYSIS ON EVERY ENTRY
After you write, an on-device LLM reads between the lines. It surfaces emotional patterns, cognitive habits, and growth you might not see yourself. Entries save instantly. The AI works quietly in the background.
BEHAVIORAL PATTERNS
CortexOS tracks the cognitive patterns and emotional rhythms in your writing over time. Rumination, self-compassion, stress responses, growth. Trend chips show what's emerging, fading, stable. Nothing gets labeled or diagnosed. Just named, so you can notice it yourself.
SELF-AWARENESS CARD
What CortexOS has learned about you. Themes, tendencies, cognitive habits, growth moments. Written entirely by the on-device AI. Visible only to you.
AI REFLECTIONS
Talk through what's on your mind by text or voice. The AI remembers your themes and asks questions that help you go deeper. Without judgment, without your words ever leaving your phone.
VOICE JOURNALING
Speak instead of type. WhisperKit transcribes on-device. No internet needed.
INSIGHTS & PATTERNS
Track 20+ emotions over days, weeks, and months. See mood trends, spot triggers, find connections between life events and how you feel. You decide what to do with them.
CHAPTERS
Every week becomes a chapter in your story. Auto-titled, themed, and summarized by AI from your entries.
NEW: MIND WRAPPED
A shareable card deck at entry milestones (25, 50, 100, 250, and beyond) and at year-end. Every card stamped with your entry count and "0 bytes sent anywhere". Share any card as an image.
YEAR IN REVIEW
Once a year, CortexOS turns your entries into the story of your year. Your emotional arc month by month, your chapters, your themes, the growth you might have missed. Built from your own words, on-device.
SMART NOTIFICATIONS
Your prompts and reminders aren't generic. They pull from what you've been writing about and the patterns CortexOS has noticed. Like a quiet tap from someone who knows you.
ENTRY ECHOES & GHOST TEXT
Old entries bubble up to remind you what you've already told yourself, and stay put on the entry once they appear. A gentle prompt fades in when the page sits empty.
THERAPIST REPORTS
A shareable PDF of your emotional patterns and cognitive trends. No journal content included. Just the insights your therapist actually needs.
PRIVATE BY DESIGN
- AES-256-GCM encryption on every entry
- Zero-knowledge cloud backup (we can't read your data)
- Pattern history travels with you across device restores, end-to-end encrypted
- On-device AI. Nothing sent to servers.
- Screen recording, AirPlay, and mirroring blocked at the system level
- No email, no password. Recovery phrase only.
- Face ID / Touch ID
- No tracking. No ads. No exceptions.
Built by a solo developer founder in Malta, Europe. No investors, no ads, no data deals. A journal that is yours alone. Enhanced by AI.
AI Disclosure: https://cortexos.app/ai-disclosure
Trust Center: https://cortexos.app/trust
Privacy Policy: https://cortexos.app/privacy
Terms of Use: https://cortexos.app/terms
Whitepaper: https://cortexos.app/whitepaper
Your Mind, Encrypted.
Ratings & Reviews
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This update is about trust and control: an AI that handles the hard moments with more care, and gives you more say in what it remembers.
Tell it when it's wrong
If CortexOS ever reads you wrong, say so during a reflection and it lets that read go for good, everywhere in the app. You can see and clear everything you've corrected in Settings.
Set topics off-limits
Not ready to dig into something? Tell the AI to leave a topic alone and it won't raise it again, in reflections, analysis, or anywhere else. It's listed in Settings whenever you want to change your mind.
Reflections that stay with the moment
Deep Analysis and reflections now focus on what you actually wrote, instead of pulling your whole history into every entry. When a past entry genuinely connects to today, it still surfaces as a throwback. The big-picture view of your patterns stays on your Self-Awareness card.
Gentler on the hard days
On a heavy day, CortexOS holds back the streaks, milestones, and upbeat nudges that don't fit the moment. And if you're going through something dark, it steps back from analysis and quietly points you toward real support.
As always, everything stays on your device, encrypted. Your words never leave your phone.
Version 1.6.0
The developer, Orlin Ralinov Martinov, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Privacy practices may vary, for example, based on the features you use or your age. Learn More
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More