A fast, native outliner. Now smooth on large outlines, with refined keyboard shortcuts. Markdown, images, iCloud sync. One-time purchase.
Kosshi is a fast, native outliner. Simple and smooth on large outlines.
Available on Mac, iPhone, and iPad — one purchase covers all three.
Outliner
Hit Tab to indent and build a hierarchy. Collapse what you don't need, drag to move things around.
Zoom In / Zoom Out
Zoom into any row and only its contents are shown. Breadcrumbs tell you where you are, and you can jump home anytime.
Markdown
Bold, italic, highlight, links, checkboxes, code blocks, and LaTeX math all render right where you type. Formatting markers only appear while editing — move away and they're gone.
Images & Files
Add images by pasting or dragging, and resize however you want. PDFs and videos show as inline previews too.
Apple Pencil Sketches
Draw sketches with Apple Pencil on iPad. They sync to Mac and iPhone through iCloud.
Search
Cmd+F to search your whole outline. Matches get highlighted. Replace works too.
Dark Mode
Switch between light and dark themes. Automatically follows your system setting.
Tags
Use #tags to categorize and @tags for dates or status. Filter from the sidebar.
Internal Links
Type [[ to search and link to another row. Build a web of connected outlines.
Bookmarks
Press Cmd+D to bookmark a row. Bookmarks appear at the top of the sidebar.
Prose Mode
Switch a row to Prose Mode for long-form writing. Bullets disappear and children stay expanded.
Reminders & Calendar
Any @tag with a date syncs to Apple Reminders or Calendar. Use @todo(3/15), @meeting(every monday 10:00), and so on.
Keyboard Shortcuts
Collapse, move, indent — all without reaching for the mouse.
Export
Export as Markdown, OPML, or plain text. Your data is never locked in.
Auto Backup
Restore past outlines from daily backups. Feel free to delete outlines you no longer need.
iCloud Sync
When iCloud is available, your outlines sync across Apple devices via CloudKit. Data is stored in your iCloud account, and the developer cannot access its contents.
Pay Once
Built natively for speed. Launches quickly and works offline. One-time purchase covers Mac, iPhone, and iPad — no subscription, no account required. A 7-day free trial is available.
Feedback
Feature requests and bug reports are always welcome. Reach us via the contact form at https://kosshi.app/contact or on X at @shirokumamake.
I love outliners. I love native Mac apps, and I love keeping my data on my computer, not in the cloud. This checks all the boxes, and is remarkably stable for a new app. I love the single file data base approach. This is as close as Mac has come to GrandView - still the best of them all. The iPad version has a little catching up to do with the Mac version, especially in find and filter, (the found items are highlighted, but sometimes are not seen in the window as you step through them, filter doesn’t always work) but I am sure that will be fixed soon. Kosshi has already surpassed the competition. The Desktop version is 5 stars and the iPad version is 3 stars, so I am giving it 4.Edit: I think the iPad problems were user error. I am changing this review to 5 stars. For my personal use, notes like OmniOutliner would make it perfect, but that is the only change (I won’t call it an improvement) I would like to see.
Developer Response
Thank you for the thoughtful review! I’m glad you’re enjoying Kosshi. Your kind words mean a lot to me, especially given your many years of experience with outliners.
Tremendous Outlining App!
cyclezen
Kosshi is very impressive for a relatively new app. It is clearly very well thought out in terms of its clean design and rich feature set. I appreciate the reasons behind creating Kosshi as a pure, native Mac app, and that shows in the way the design flows gracefully across platforms.The developer is very active in refining and enhancing the app, and is very responsive on his forum. The one-time price is extremely reasonable, in my opinion. If you’re into outliner apps I strongly recommend that you try out Kosshi.
Best Outliner I’ve Used
mitchellsf
This is a brilliant outliner app. I use outlining a lot for various purposes and I’ve found Kosshi to be the smoothest experience. The integration between Mac and iOS versions is fantastic. I mainly write outlines on my Mac, but view/use many outlines on my iPhone. Being able to easily navigate on the phone, and add content as needed, is done in a thoughtful and intuitive way. Plus the app developer keeps adding important new features. Put simply: best outliner I’ve ever used.
Developer Response
Thank you for using Kosshi! I’m glad you’re finding it useful. I’ll keep working to make it easy to use across your Apple devices.
Great potential
iwritewords
This app has a lot of potential. I love the design; it is kind of like an offline Workflowy, which is not a bad thing.The developer is accessible and responsive, and I have seen the app improve tremendously since I first got it. I am looking forward to watching it grow.
Developer Response
Thank you for using Kosshi and for your kind words! I’m still working on many more updates, and I hope you’ll enjoy watching it grow.
What's New in 1.22.1
- On iPad with an external keyboard, you can now use the arrow keys to choose conversion candidates while typing
- Fixed issues with Undo, Redo, and Cut
- Improved scrolling smoothness while the keyboard is shown
Version 1.22.1
The developer, Junichi Sato, 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
Information
Seller
Junichi Sato
Size
31.2 MB
Category
Productivity
Compatibility
Requires iOS 17.0 or later.
iPhone Requires iOS 17.0 or later.
iPad Requires iPadOS 17.0 or later.
Mac Requires macOS 14.0 or later.
Apple Vision Requires visionOS 1.0 or later.
Languages
English and 8 more
English, French, German, Italian, Japanese, Korean, Simplified Chinese, Spanish, Traditional Chinese