For each dream you write down you can select a dream lucidity level from none to fully lucid, later you can find all your lucid dreams easily and see your improvements over time.
All your dreams are stored securely encrypted locally on your device with a password set by you. Every time you open the app you have to unlock it using your password or biometrics (Face ID iOS).
The app keeps you motivated my showing your streak of days when you wrote down at least one dream. Furthermore, every day gets a rating based on how detailed (how many words) and on how many dreams you remembered. (Both of these features can be disabled if you just want a simple journal).
The app has detailed statistics so you can exactly see your progress over time, from seeing your progress over multiple years to checking every single week since you used the app in full detail or even the most used words across all your dreams.
You can customize the app exactly to your liking, from changing the color of the app to selecting from the beautiful included background images or even selecting your own custom background image.
To make sure your dreams are safe and fully stay in your control you can either export them as an encrypted backup or if you want to access them without the app you can also export them as nicely organized PDF or Markdown files.
You can easily find any of your dreams by just searching for words you used in them, filtering by date range, lucidity level or a combination of all.