100% Offline · No Account · Data Stays on Device

Your ferments,
remembered.

Fermly is an offline logbook for people who keep a live starter and a counter full of jars. Every batch gets a real stage timeline, every culture gets a feeding clock, and every good result gets written down — so you can actually make it again.

The problem

Fermentation is time-critical. Your memory isn't.

Three jars on the counter and not one of them is labelled. Was the kraut packed on Tuesday or Wednesday? When did the starter last get fed? And that loaf everyone loved last month — what hydration was it, actually?

Unlabelled jars

Nothing on the counter has a date

Ferments run on hours and days, but the jar can't tell you when it started or when it should move to the fridge.

A hungry culture

The starter gets forgotten

A live culture needs feeding on a cadence. Miss it for long enough and you're rebuilding from scratch.

Lost formula

The good batch can't be repeated

Hydration, salt, temperature and timing are what made it work — and none of it was written down.

What's inside

A real logbook, not a checklist.

Everything below runs entirely on your phone. No account, no sync, no server to go down.

Stage timelines that fit the ferment

Sourdough runs Levain → Bulk → Shape → Proof → Bake. Kombucha runs 1F → 2F → cold crash. Each type arrives with a sensible timeline you can adjust.

A Today & Upcoming agenda

Open the app and see exactly what needs you — overdue feeds first, then the stages landing next. No notification permission required.

Live cultures with a feeding clock

Track every starter, SCOBY or set of kefir grains: feed ratio, cadence, rise percentage and the full feeding history.

Insights computed on device

Batches per month, average rating, starter-activity trends and a breakdown of what you actually ferment — all from your own data.

Streaks, goals and badges

Keep a feeding streak alive, set a weekly batch goal, and unlock milestones from your first ferment to a thirty-day culture streak.

Search, tags, filter and sort

Full-text search across batches, notes and recipes. Filter by status or ferment type, sort by due date or rating, and pin the ones you love.

Recipes that make it repeatable

Save hydration, salt, temperature, ingredients and method — then hit "Brew this" to start a new batch with the numbers already filled in.

Export as JSON or CSV

Your log is yours. Write a full backup or spreadsheet-ready CSVs to your own files and share them anywhere — no cloud in the middle.

Restore in one tap

Moving to a new phone is a backup and a restore — every batch, recipe, culture and feeding comes back intact.

Light, dark and your accent

Five accent colours, three layout densities and a full dark theme — set it once and it sticks.

Archive, trash and undo

Every delete offers an undo, bulk actions handle a whole shelf at once, and nothing disappears without a way back.

Private by construction

Feeding logs are encrypted at rest, there is no account to create and no analytics code to opt out of — because there is none.

Privacy

Nothing leaves your phone.

Fermly declares exactly one permission — internet access — and uses it for exactly one thing: loading this privacy policy inside the app. Your batches, recipes, cultures and feeding logs never travel anywhere. The Play Data Safety declaration is "no data collected", and it is accurate.

Start your logbook.

Free. No ads, no subscription, no account. Bring your own jars.

Android 5.0 and up.