Privacy Policy — MyChangeLogy

Effective date: 2 September 2026 App: MyChangeLogy (Android) Publisher: developer LNOE Contact: lunicoworld@gmail.com

Summary

MyChangeLogy has no user accounts, and everything you enter — your goals, your marks, your notes — stays on your device. There are no ads and no advertising identifier.

The one exception is anonymous usage statistics — a record of which steps and screens are used, so we can see where the app is failing people. It runs from first launch and there is no setting to switch it off; uninstalling the app ends it. What it contains, and what it can never contain, is set out in full below, because that list is the actual limit on what is collected.

Two other things involve someone else. If you buy Premium, Google Play handles the payment and we never see it. If you set your water goal to fill itself in, the app reads one number a day from Health Connect or from our own MyAquaLogy — and what it reads stays on your device.

What the app stores (on your device only)

To do its job, the app saves the following in local storage on your device:

Your goals (habits, commitments, limits) and their settings.
Your daily marks, amounts, and results.
An optional note you attach to a day.
App preferences (language, theme, reminders, app‑lock setting).
Whether Premium is active — a single flag, and nothing else about the purchase.

This information never leaves your device except through a backup you create (see below).

Usage statistics

Running from first launch, for everyone, with no in-app setting to turn it off. We have chosen to describe exactly what is measured rather than offer a switch, so the list below is not a summary — it is the whole of it.

The app records the shape of what you did, never what it was about. These are all the events it sends:

Which setup step you reached, and, when setup finishes, how many goals you made, whether you asked for reminders, and roughly how long it took.
That a goal was added — which of the three kinds, whether it came from the ready-made list, and whether it has a numeric target. Never which preset, and never what you called it.
That a goal was marked for a day, and whether that day came out completed, partial or missed.
The first time a goal was marked, and roughly how old the goal was by then.
That a goal was paused, completed or archived, and roughly how old it was.
That the app was opened on a day, with roughly how many goals are running and how many of them are already marked.
That a run carried on across a gap, and roughly how long the gap was.
Whether a permission — notifications, or hydration — was granted or refused.
That a reminder was shown, for which kind of goal, and which part of the day it belongs to.
That the Premium screen was opened, and what led there.
How the nightly tracker read ended: something read, nothing to read, or no permission.
That a backup was created or restored, and whether it worked.

Durations, counts and ages leave as ranges — "2–6 days", "4–7 goals" — never as exact figures. Screen views are not collected at all.

Never sent, in any circumstance: the name you give a goal, the note you attach to a day, any amount or target you enter, any date you choose, backup file names or passwords, and anything read from Health Connect. The app never asks for your name, and has nowhere to keep one.

This is processed by Google Firebase (Analytics and Crashlytics) as our processor. Firebase assigns your installation a random identifier and records the technical details any network request carries — approximate region, device model, app version, operating system. That identifier is not linked to a name or an account, and it is deleted when you uninstall. We use it to see where people get stuck; it is never used for advertising or profiling, and it is never sold.

The in‑app "Dynamics" trends are calculated locally on your device and are not sent anywhere.

Crash reports

When the app crashes, Crashlytics sends its own report: where in the code it failed, and the technical details of the device, the operating system and the app version. Nothing is attached naming the goal you were looking at or the screen you were on, and no user identifier of ours is attached — we have none to attach.

One failure you would never see for yourself is reported as well: a backup that would not restore. It goes out as a marker carrying two words — which part gave up, and how — with no stack from the failure itself and deliberately not the error the app caught, because what is in memory at a failed restore is a file path and a password prompt. The nightly tracker read is not reported this way; how it ended is one of the ordinary events listed above.

Purchases

Premium is sold through Google Play, as a subscription or as a one-time purchase. When you buy:

Google processes the payment and receives whatever its own terms describe — your Google account, payment method, order and purchase token. We never receive or store your payment details.
The app asks Google Play what it currently offers, so that prices can be shown in your own currency. Those prices come from Google; the app holds none of its own.
Once a purchase is confirmed, the app keeps one local flag: Premium is active. Nothing else about the purchase is stored on the device.
Ending Premium removes nothing. Your goals, your history, backup and restore keep working.

The app includes the Google Play Billing Library (Google LLC), which is what makes a purchase possible; it speaks to the Google Play app already on your device. Google's handling of the payment is governed by the Google Privacy Policy and the Google Play terms.

Backups

You can export a backup file yourself, and choose whether to protect it with a password. With a password the file is encrypted (AES-256-GCM, key derived with PBKDF2-HMAC-SHA256); keep that password safe, because it cannot be recovered and without it the backup cannot be opened. Without a password the file is written unencrypted, and anything that can read your files can read it — which is worth knowing if you keep it in a folder that syncs somewhere.

You decide where it is saved (for example, your device storage or a cloud folder of your choosing via Android's file picker). The developer never receives this file. Restoring a backup replaces what is currently in the app with what is in the file.

Permissions

These are every permission the installed app declares, and what each is for:

Notifications (POST_NOTIFICATIONS) — to show the reminders you set for your goals. Reminders are generated locally on your device.
Run at startup (RECEIVE_BOOT_COMPLETED) — to re‑schedule your reminders after the device restarts.
Biometrics / device credential (USE_BIOMETRIC, USE_FINGERPRINT) — only if you enable App lock, to unlock the app. Biometric data is handled by Android and is never accessed by or shared with the app.
Read hydration (android.permission.health.READ_HYDRATION) — only if you set a water goal to be filled in from a tracker. See below.
Read health data in the background (android.permission.health.READ_HEALTH_DATA_IN_BACKGROUND) — so that the day's water fills itself in without your opening the app. It serves that one reading and nothing else.
A day from MyAquaLogy (com.myaqualogy.app.permission.READ_HYDRATION_DAY) and a day from MyFocusLogy (com.myfocuslogy.app.permission.READ_FOCUS_DAY) — to read one day's figure from our other apps, if you have them and set a goal to be filled in from one. See below.
Billing (com.android.vending.BILLING) — to offer and complete a Premium purchase through Google Play.
Internet (INTERNET, ACCESS_NETWORK_STATE) — for two things: sending the usage statistics described above, and asking Google Play about prices and purchases. Nothing you write goes over either.
Wake lock (WAKE_LOCK) — held by the Google and AndroidX components while a short background task finishes, so the device does not sleep halfway through it.
One permission carrying the app's own name (…DYNAMIC_RECEIVER_NOT_EXPORTED_PERMISSION) is generated by AndroidX and exists only to keep the app's internal broadcasts from being readable by other apps.

The app does not request access to your contacts, precise location, microphone, camera, files or calendar, and it declares no advertising identifier.

Health data (Health Connect)

If — and only if — you set a water goal to be filled in from a tracker, the app reads how much water you drank on a given day. You are asked for this permission at the moment you make that choice, and the goal keeps working by hand if you decline.

Read only. The app holds no write permission for health data and never writes anything back: what it reads it stores as one day's amount on your own device, in the same local database as everything else.
Only hydration. No other health or fitness data is requested or accessed — not steps, not heart rate, not sleep, not weight.
Only the days that goal covers. Reading starts from the day you turned the tracker on, and stops the moment you switch the goal back to being marked by hand.
Read in the background. So that a day fills itself in without you having to open the app, the read also runs while the app is closed — once a night, for the day just ended. That is the whole of what the background permission is for; nothing else is read, at no other time.
It does not leave the device. What is read is written into your own day, and stays there. The app does reach the network — for the usage statistics and for Google Play purchases — and health data is excluded from both: no amount, no date, and nothing read from Health Connect is ever part of a statistic or a crash report. It is shared with neither the developer nor any third party.
Withdrawing. Revoke the permission at any time in Health Connect (Settings → Health Connect → App permissions), or switch the goal back to By hand in the app. Neither is retroactive: amounts already written into your days stay there until you delete the goal or the app.

Data read from Health Connect is used for one purpose — showing whether a day met the water goal you set. It is never used for advertising, analytics, profiling, or sold to anyone.

Data from our other apps

If you have MyAquaLogy or MyFocusLogy installed, a goal here can be filled in from one of them instead of by hand. You grant that as an ordinary permission when the app is installed, and the goal keeps working by hand if you would rather it did.

What crosses is deliberately small: for one date, how much was done that day, what that day was aiming at, and the share of the two. Nothing about drinks, sessions, times, streaks, or anything else those apps know. It is read directly from the app on your device — it does not travel over the network — and what is read is stored in your own day here and goes no further.

Data retention and deletion

Your data lives only on your device. To delete it, clear the app's storage (Android Settings → Apps → MyChangeLogy → Storage → Clear data) or uninstall the app. Any backup files you exported remain wherever you saved them until you delete them yourself.

Children's privacy

The app is not directed at children. Nothing you write is collected, and no profile is built of any user, including children: the usage statistics described above record the shape of what was done, never who did it or what it was about.

Security

Data is stored in the app's private storage. A backup is encrypted with your password when you set one, and written unencrypted when you choose not to. You can additionally protect the app with App lock (device biometrics or PIN).

Changes to this policy

If this policy changes, we will update the text and the effective date above. Material changes will be reflected in the app's store listing.

Contact

Questions about privacy? Contact lunicoworld@gmail.com.