Starter Diary: Never Lose Track of Your Sourdough

Every sourdough baker has had the same sinking moment: you open the jar on bake day, see a flat, liquid-y mess, and realize you missed a feeding two days ago. The starter isn't dead, but the dough definitely won't rise tonight. Starter Diary is a small, focused app that lives on your phone and keeps an honest record of every feeding so that moment stops happening.

It's not a sourdough encyclopedia or a recipe manager. It does one thing well: it tracks your feedings, shows you how long ago the last one was, and lets you compare ratios over time. Open the app right now in the frame below and poke around, then read on for the thinking behind it.

The problem with relying on memory

A healthy starter on the counter needs feeding every 12 to 24 hours depending on your kitchen temperature. That's a reasonable cadence, until life gets in the way. You feed it Monday morning before work, then forget whether you fed it Tuesday or just thought about feeding it. By Wednesday the hooch layer has formed, the smell is off, and you're not sure if you should discard and start fresh or just power through.

Most bakers solve this with a sticky note on the jar, a photo in their camera roll, or a note in a general notes app. None of those tell you the hydration percentage you used last time, and none of them show you a pattern across two weeks of feedings. Starter Diary keeps that record automatically the moment you log a feeding.

Logging a feeding takes ten seconds

The core of the app is the feeding form: flour grams, water grams, an auto-filled timestamp, and an optional note. Enter 50g flour and 50g water and it immediately shows you 100% hydration and a 1:1 ratio. Change the water to 35g and you're at 70% hydration, a stiffer dough-style starter. That instant feedback is genuinely useful when you're experimenting with hydration levels and want to remember what you actually used versus what you planned.

The hours since last feed counter sits at the top of the main screen, paired with a simple hunger indicator. It's not alarm-based, it doesn't nag you. It just answers the question you actually ask yourself, which is: how long has it been? Try logging a feeding in the live demo above and watch the counter reset.

Comparing feedings over time

Single feedings are easy to eyeball. Patterns across a week or two are harder to hold in your head. The charts in Starter Diary show two things: how many times per day you're actually feeding the starter, and how your hydration has drifted over the same period. If you're running a higher-hydration starter in summer heat and a stiffer one in winter, that shows up clearly in the hydration line.

This is especially helpful when you're trying to dial in a consistent result before a big bake. If the last three bakes that turned out well all came from a starter fed at 90 to 100% hydration, twice a day, for three days prior, you now have the data to recreate that. It's not scientific in a lab sense, but it's specific enough to be useful.

The app seeds example data on first launch so the charts aren't empty when you open it for the first time. You can see immediately what a healthy feeding rhythm looks like visualized, rather than staring at blank axes.

Fully offline, nothing to sync

Starter Diary stores everything on device. There's no account, no cloud sync, no server to be down when your starter is hungry at 6am. This was a deliberate choice: a feeding log is personal data that doesn't need to leave your phone, and removing the network dependency means the app is always fast and always available.

The trade-off is that your data lives on one device. For most home bakers with one starter and one phone, that's fine. The simplicity is the point. This isn't an app you manage, it's an app you glance at while standing at the kitchen counter with floury hands.

Who this is for

If you keep a starter on the counter and you've ever blanked on when you last fed it, this app is for you. It doesn't assume you're an expert, and it doesn't try to teach you sourdough basics. It assumes you already know what you're doing and just want a lightweight record that's easier than a sticky note and more structured than a camera roll.

Hydration experimenters will get the most out of the ratio tracking. If you only keep one starter at a fixed ratio and feed it on a rigid schedule, you might find you don't need it at all. For everyone in between, it fills a real gap that no other tool quite covers in such a small, focused package.