Nenrin — Pen & Ink Collection

Nenrin is a fountain pen and ink collection app for iPhone: your pens, your inks, and which pen is inked with what, right now. No account, no tracking. Pay once, yours forever.

年輪 — tree rings. A collection should grow slowly and stay yours. Not a database. A place.

WHAT IT KEEPS
Every pen — brand, model, nib, filling system, photos, and the story of how it came to you.
Every ink — bottles with their levels, sheen and shimmer kept as colours, on a shelf that behaves like a shelf.
What's inked — which pen carries which ink, since when, and when it's time to clean.
The pens you're hunting. And one card of the whole collection, made for sharing.

BRING YOUR COLLECTION WITH YOU
Already keeping your pens in another app or a spreadsheet? Nenrin reads your CSV export and your collection walks in with you — pens, inks, details intact. Import is free for everyone, at every tier, always. Nothing held back, nothing behind a door.

THE COLLECTION, BEAUTIFULLY KEPT
Add a pen in four taps — a deep catalogue of brands, models and colorways meets you as you type, and anything it doesn't know you can always write by hand. Photos framed the way you choose, nib and filling system at a glance, and room for the story — where it came from, what day it was. The things a spreadsheet forgets.

INKS THAT LIVE
Your bottles stand on a shelf — many in their brand's own shape — and behave like bottles: the ink leans when your phone tilts, sloshes when you tap, settles its shimmer while you're away. Fill levels move a real waterline. Sheen and shimmer are captured as colors, not checkboxes.

THE ROTATION
Ink a pen — from the bottle, a converter, or a cartridge — and it enters the rotation. See what's inked with what and for how long, mark a pen for cleaning, and let a quiet reminder tell you when a fill has sat too long.

GRAILS
The pens you're hunting. A target, what you've set aside, and the notes — where you spotted it, what the nib should be. When the day comes, one tap converts the grail into an owned pen with its story intact.

THE PALETTE
One tap composes your collection into a card — your pens as a quiet palette, light or dark — made for the communities you're already part of.

YOURS, QUIETLY
- Syncs through your own iCloud. No accounts, no feed, no AI.
- No analytics, no ads, no tracking. We can't see your pens.
- Export everything — records and photographs — as one copy you can open anywhere. Free forever. Your data is yours.

Free for one pen and one ink — everything included, import included. Nenrin Pro is a single purchase (no subscription, ever): unlimited pens and inks, alternate app icons, and shares without the small mark.