TRANSPARENCYIf it's free, are you the product?
No. Here, in plain language: how Plumm makes a living, what we collect, and what we'll never do.
Model: premium, never your data
Plumm will be funded by an optional premium plan. Not by ads, not by data resale.
Transparent algorithm
The prediction algorithm is publicly documented (CLAUDE.md, repo).
Public roadmap
We say what we're building. You can follow along.
How Plumm makes a living
Today, Plumm is free. Zero revenue, zero ads, zero resale.
A future Plumm+ plan (paid, optional) is in the works: it unlocks advanced features without ever locking what's already free. Clear pricing in-app, payment via the App Store or Google Play, no subscription traps.
That's our only model. No ads, no brand deals, no data resale — ever.
What we'll never do
- Sell, rent or share your data (advertiser, insurer, employer, government). No exception.
- Put targeted ads in the app.
- Add a tracker (Google Analytics, Facebook Pixel…).
- Trap you with dark patterns to make you pay.
- Hide our subprocessors or their country.
What we collect (and don't)
We do NOT collect (by default): • your cycle data — it stays on your phone (unless you enable cloud backup) • your IP, cookies, advertising identifier • any usage metric
We collect only if you enable an option: • messaging / idea board: the content of your messages, an anonymous device identifier, a notification token; for the idea board, your ideas/votes/comments (public) and your first name • cloud backup: an encrypted copy of your cycle data + your account email
All the detail on the Security page.
Our roadmap
What we're preparing, in order of priority: • App Store / Google Play release — the NEW GAME company is formed; we're waiting on the Apple Developer account, then we ship. • PIN / Face ID — code ready, shipping in the first build. • ✅ End-to-end encrypted direct transfer between two phones + opt-in cloud backup — so you never lose your data when changing phones (shipped; the transfer is end-to-end encrypted, the cloud backup is optional). • Plumm+ — optional paid plan (date TBD).
We update this list as we go.
Our algorithm, in the open
Plumm's prediction algorithm is detailed on our Science page and in the project's public docs. A question? Email hello@plumm-app.com — we reply.
It's the minimum when you ask people to trust you with their health data.
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