LogZero

A new kind of personal tracker

Track Everything.
Share Nothing.

The private, all-in-one iOS tracker for moods, meds, food, exercise, meditation, weight, todos and more. Safe, private and secure by default.

Scan with your phone
to open in the App Store

iPhone & iPad · iOS 16+ · No account required

  • 100% on-device
  • No accounts
  • No ads
  • No tracking
  • App Privacy: Data Not Collected

Why LogZero is different

Most "private" trackers still upload your data.

For LogZero, privacy is not an afterthought - it's in the app's DNA.

App Category Privacy Security All-in-one Pricing
Mood Trackers Cloud, analytics Moderate No Freemium · ~$40/yr
Food Trackers Cloud, ads, analytics, data sales Moderate, breach history No Freemium · ~$60/yr
Exercise Trackers Cloud, ads, analytics, data sharing, social-default Moderate, breach history No Freemium · ~$50/yr
Meditation Trackers Cloud, analytics, ads in free Low No Freemium · ~$65/yr
Todo Trackers Cloud, analytics Low No Freemium · ~$50/yr
Medication Trackers Cloud, analytics High, some HIPAA-aware No Freemium · ~$40/yr
Weight Trackers Cloud, analytics Moderate, breach history No Freemium · ~$30/yr
LogZero That's us On-device, no telemetry Very High, local sandbox, AES-256 at rest, Argon2 KDF AES-256-GCM exports, biometrics & passcode support Yes Free · $5/mo · $35/yr · $99 lifetime

  • LogZero

    That's us
    Privacy
    On-device, no telemetry
    Security
    Very High, local sandbox, AES-256 at rest, Argon2 KDF AES-256-GCM exports, biometrics & passcode support
    All-in-one
    Yes
    Pricing
    Free · $5/mo · $35/yr · $99 lifetime

  • Weight Trackers

    Privacy
    Cloud, analytics
    Security
    Moderate, breach history
    All-in-one
    No
    Pricing
    Freemium · ~$30/yr

  • Medication Trackers

    Privacy
    Cloud, analytics
    Security
    High, some HIPAA-aware
    All-in-one
    No
    Pricing
    Freemium · ~$40/yr

  • Todo Trackers

    Privacy
    Cloud, analytics
    Security
    Low
    All-in-one
    No
    Pricing
    Freemium · ~$50/yr

  • Meditation Trackers

    Privacy
    Cloud, analytics, ads in free
    Security
    Low
    All-in-one
    No
    Pricing
    Freemium · ~$65/yr

  • Exercise Trackers

    Privacy
    Cloud, ads, analytics, data sharing, social-default
    Security
    Moderate, breach history
    All-in-one
    No
    Pricing
    Freemium · ~$50/yr

  • Food Trackers

    Privacy
    Cloud, ads, analytics, data sales
    Security
    Moderate, breach history
    All-in-one
    No
    Pricing
    Freemium · ~$60/yr

  • Mood Trackers

    Privacy
    Cloud, analytics
    Security
    Moderate
    All-in-one
    No
    Pricing
    Freemium · ~$40/yr

Comparisons based on analysis performed in mid-2026, comparisons utilize several of the top trackers for each category.

Convinced? Try LogZero free on iPhone.

What you can track

Nine tracker modules. One app.

Nine tracker modules, one private home. Turn on what you care about; ignore the rest.

Mood

Log moods, emotions, and activities. None of it leaves your phone.

Medication

Schedule meds, hit adherence, get reminders. Locally.

Food

Calories, macros, and presets. Never sold to brokers.

Exercise

Time and log workouts; track daily targets. Privately.

Meditation

Real-time countdown in the Dynamic Island. Streaks on-device.

Weight

Daily weight, trend charts, lbs or kg. Yours alone.

TODO

Tasks with priorities, tags, and celebrations. Fully local.

Correlations

See what affects your mood. Math runs on your phone.

Dashboard

Today, streaks, weekly deltas, and one quiet insight per day.

Try them all.

Free to start. No account required.

Sleep × Mood Strong

r = 0.62 · 30 days · same-day mood vs. previous-night sleep

Caffeine × Mood Weak

r = -0.18 · 30 days · no meaningful pattern detected

Correlations · Beta

See what actually affects your mood.

LogZero computes statistical correlations between your trackers (sleep vs. mood, exercise vs. weight, caffeine vs. anxiety, etc) entirely on your device. Discover the patterns no one else sees, because no one else gets to see them.

About correlations

Nine private tracking modules. One iPhone app.

App Store privacy label

Nothing collected. Nothing tracked. Verifiable.

The privacy promise isn't a footer link. It's what Apple shows before you download.

Read the full privacy posture on our privacy page or read the policy itself.

How it works

Three steps. None of them harvest your data.

  1. 01

    Download

    Install from the App Store. No website signups, no account screen, no email request.

  2. 02

    Log what matters

    Pick the trackers you want. Mood, food, meds, exercise, weight, todos. Turn on what you care about; the rest stays out of view.

  3. 03

    See patterns

    Streaks, weekly deltas, correlations, "worth noticing" insights. All computed on your phone using local algorithms. All visible only to you.

Common questions

Security and privacy are always first.

Is LogZero really private?
Yes. Everything you log is stored on your device and encrypted with AES-256 symmetric key encryption. The app makes zero network requests for your private data. We don't see it, sell it, or share it. The App Store privacy label declares "Data Not Collected" across every category.
Does LogZero require an account?
No account. No email. No sign-up. Open the app and start logging. Your data lives where it should: on your phone.
What can I track in LogZero?
Mood, medications, food (with calories and macros), exercise, meditation, weight, todos, and custom metrics. Plus statistical correlations between datasets, all computed locally on your iPhone.
How do I move my data to a new phone?
Export to a JSON file from Settings → Backup. Move the file via AirDrop, iCloud Drive, or any way you'd move a photo, then import on the new device. You stay in control of the transfer.
What's the difference between Free, Pro, and Lifetime?
Free gives you every module with limited customization and limited advanced functionality. Pro unlocks the full app at $5/mo or $35/yr. Lifetime is a one-time $99 purchase — no renewals, ever.

Your whole life,
on your device.

No account. No commitment. Your data stays yours.