Build a habit tracker app that stays on your phone

The screens a habit tracker needs

Today: Every habit due today with a large tap target to mark it done. Undo is one tap away. This is the screen the app opens on.
Add or edit a habit: A name, how often (daily, certain weekdays, or a number of times per week), an optional target such as 20 minutes or 8 glasses, and a colour.
History: A calendar grid per habit, filled squares for done days. People like seeing a year of squares more than any number.
Insights: Current streak, longest streak, and completion rate over the last 30 days, with a simple bar or line chart.

Everything else is optional. Reminders, journaling, mood scores and badges all add friction, and most people who abandon trackers do so because the app asks too much of them each day, not too little.

Streaks without the guilt

A streak counter motivates until it breaks, and a single missed day resetting 60 days to zero is the moment many people give up for good. Decide your rules before you build:

Weekly targets instead of daily. "Run three times a week" can't be broken by a rest day.
Skip days. A planned skip (holiday, illness) that pauses the streak rather than ending it.
Grace period. Let yesterday be marked done until midday today, for people who forget to tick at night.
Show the long view too. "27 of the last 30 days" survives a miss where a streak doesn't.

Also decide what "today" means. Someone checking in at 1 a.m. usually means yesterday. A configurable day-start hour (say 4 a.m.) solves this quietly.

Starting from Ritualist or from a sentence

Anticode's template gallery includes Ritualist, a habit tracker written by Anticode's model. Using it copies the whole app into your project with no model call and nothing off your limits, and you can then reshape it with change requests: "add weekly targets", "make the history a year grid", "use green for done days".

To build your own from scratch, describe the habits, the rules and the feel: "A daily habit tracker for a writer: words written as a number target, reading as yes/no, and no-phone mornings. Weekly view first. Streaks with one skip per week. Calm, dark, large tap targets." The model writes the tracker as one app that runs in the browser, with charts drawn in code and the check-in screen designed for one-handed use.

Where your data is kept

Anticode apps run in a sandbox with no network, so a habit tracker built here never sends your check-ins to a server, including Anticode's. Habits and history are saved in the browser you use, and they're there next time you open the app on that device. For a private habit like therapy exercises or drinking less, that's an advantage worth stating on the welcome screen.

Every published site can also be installed as an app on phones and desktops, with its own icon and an offline fallback. Installed on your phone's home screen, the tracker opens like any other app, which is exactly the low-friction check-in you want.

The trade-off: no sync

Because nothing leaves the device, there's no sync. Check in on your phone and your laptop shows nothing. Clearing the browser's site data, or using a private window, loses the history. Two habits help: use the tracker on one device only, and ask for an export and import button (a file you save and load yourself) so you can move your history or keep a backup.

What it can't do

No push reminders. The app can't send notifications when it's closed. Use your phone's own reminders or calendar for nudges.
No accountability partners. Sharing progress with a friend or a coach needs shared data, which the sandbox doesn't have.
No health data. It can't read steps, sleep or heart rate from a watch or a health app; anything like that is typed in.
Not a product for many users. If you want to launch a habit app to the public with accounts and sync, the Next.js export gives a developer a starting point with a database and sign-in.

Questions people ask

Is the habit tracker app private?

Your check-ins stay in your own browser on your device. Anticode only sees that the published page was viewed, counted without cookies.

Can I share my tracker with family?

You can share the link, and each person gets their own empty tracker on their own device. Their data and yours never mix.

Can it track numbers, not just yes or no?

Yes. Ask for habits with a numeric target (minutes, pages, glasses) and a chart of the values over time.