Browser: Free. Native app for iPhone, iPad and Mac: €14.99/$12.99 at launch (regular €19.99/$19.99), one-time purchase across all three devices, no subscription.
Not given
Key features
Fully offline with no server required
Real folders on disk and Markdown files
Automatic version history with restore
Sync via user's own cloud folder (iCloud, Dropbox)
Nested folders to any depth
Freehand drawing with pen and color
Magnetic arrows for connecting elements
Full-text search across all folders
Interactive to-do lists on canvas
Grid paper with square or rectangular cells
Graph paper with optional axes
Isometric grid paper for 3D sketching
Lined paper with custom spacing
Dot grid for bullet journals
Cornell notes layout
Coordinate plane with labeled axes
Engineering paper and staff paper layouts
PDF and SVG export formats
Real page dimensions and custom measurements
What makes it different
No account or server: your data never leaves your device
Real files you own: folders are real folders, documents are Markdown files
Works fully offline with no internet dependency
Automatic sync through your own cloud (iCloud or Dropbox)
Native apps for iPhone, iPad and Mac showing full canvas
visualOS
MyPaperKit