Adam Bandel


Habit Ledger Devlog: Building a Quantified Self Tracking App

August 28, 2025 • Related to Habit Ledger

Context: quantified-self brainrot (affectionate)

I’ve been part of the quantified self “track everything” world for over a decade, and I genuinely love tracking data about myself. Over time I’ve relied on a bunch of tools–ActivityWatch for computer history, sleep trackers like Sleep as Android (and currently Fitbit), plus habit/exercise/event tracking (reading, meditation, workouts, etc.).

The problem: exports that make me want to walk into the ocean

For a long time, I used an app called “Keep Track.” Then I finally bit the bullet and tried to export my data… and the exports were horribly horribly formatted. JSON, CSV, text–doesn’t matter: it’s a mess.

Why that’s unacceptable (for me)

I need clean data that can go straight into my metrics dashboard and be parsed cleanly over time–tens of thousands of datapoints, not “eh close enough.” Also: I needed habit entry to be stupid easy, because if it’s not frictionless, I won’t keep up with it.

The solution: Habit Ledger

So I built Habit Ledger–a very simple app (not on the App Store; just a personal APK).

What it does:

Current state

It’s intentionally minimal: quick entry, clean export, done. “It’s really that simple.”