Expenseum Privacy policy

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Privacy Policy

Last updated 4 September 2026 · Applies to Expenseum for iOS, iPadOS and Android

The short version. Your books, entries and attachments are stored on your own phone. You don't need an account to use Expenseum. Things only leave your device when you ask them to — a backup to your Google Drive, a split book shared with friends, a question to the AI assistant, or a post in the community forum. We do not sell your data, and the app contains no third-party advertising SDKs.

Who we are

Expenseum is built and operated by Appentium. In this policy, “we”, “us” and “our” mean Appentium; “you” means the person using the app.

For anything to do with privacy, write to info@appentium.com. We are the data controller for the information described below.

What stays on your device

Expenseum is offline-first. The following are written to a database in the app's private storage on your phone or tablet, and are not uploaded to us:

If you never sign in and never turn on backup, this data stays on your device for its whole life — and deleting the app deletes it.

When you create an account

An account is optional. You only need one for Google Drive backup, split books, collaboration, the community forum, referrals or a Plus subscription. Accounts are handled by Firebase Authentication (Google LLC). You can use Sign in with Apple, sign in with Google, or use an email address and password; some flows verify your email with a one-time code.

When you sign in we store your user ID, email address, and — if your provider supplies them — the display name and profile photo. If you use Sign in with Apple and choose to hide your email, we only ever see Apple's private relay address.

What we collect, and why

DataWhy we have it
Account identityuser ID, email, name, photoTo sign you in, show you to people you share books with, and route invitations.
Split & shared book contentsexpenses, shares, balances, commentsStored in Firebase Firestore so every member of the book sees the same balances. Only members of a book can read it.
Collaborator invitationsinvitee email addressTo deliver the invitation and attach the right person to the book once they accept.
Community forum poststitle, body, comments, votes, attachmentsForum content is public inside the app by design. Don't post anything you want kept private.
Subscription statepurchase token or receipt, plan, expiryTo verify your Plus purchase with the App Store or Google Play and unlock features on your devices.
Referral codesyour code, codes you redeemedTo credit the reward to both sides and to stop the same code being redeemed twice.
Push tokenHeld by OneSignal so we can notify you about split-book activity and reminders you asked for.
Usage analyticsscreen views, feature events, device model, app version, coarse regionFirebase Analytics, aggregated, so we can see which features are used and where the app breaks. Not tied to your transaction data.

Expensight AI

Expensight is the in-app assistant. It runs only while you have the assistant open and send it a message.

Backups to your Google Drive

Backups are optional, and they go to your Drive, not to us. When you connect Drive, the app requests the drive.file scope, which means Expenseum can only see and manage the files it created itself — it cannot read the rest of your Drive.

You can also back up to a file on your device. Backup history shows dated restore points so you can choose exactly which one to restore. Deleting a backup file from your Drive deletes it for good; we hold no copy.

Sharing a book with other people

Split books and collaboration are shared by nature. When you add someone to a book:

Your other books stay private. Sharing one book never exposes the rest.

Device permissions

Every one of these is asked for at the moment it's needed, and the app works without them.

Payments

Expenseum Plus is sold through the Apple App Store on iPhone and iPad, and through Google Play Billing on Android. We never see or receive your card number — the store handles the payment and tells us only whether a purchase is valid, which plan it is, and when it expires. We verify that purchase on our server so Plus unlocks on your devices.

Apple and Google process your payment under their own privacy policies. We do not receive your billing address, card details or store account password.

What we never do

How long we keep things

Deleting your data

In the app, open Settings → Account → Delete account. You'll be asked whether to also wipe the books stored on the device, or keep them and only remove the account. Deleting the account removes your profile, subscription record, referral record and forum authorship from our systems.

Content in a shared book may remain visible to the other members afterwards, because it is part of their record of who owed what. If you want something removed from a shared book, remove it before you delete the account, or ask us at info@appentium.com.

Your rights

Depending on where you live, you may have the right to access, correct, export or erase your personal data, to object to or restrict processing, and to complain to your local data protection authority. Most of this you can do yourself in the app; for anything else, email info@appentium.com and we'll respond within 30 days.

Service providers & international transfers

We rely on a small number of processors to run the app: Google (Firebase Authentication, Firestore, Storage, Cloud Functions, Remote Config, Analytics, Gemini API, Drive, Play Billing), Apple (Sign in with Apple, App Store purchases) and OneSignal (push delivery). These providers operate globally, so your data may be processed in countries other than your own, including the United States, under the safeguards those providers offer.

Children

Expenseum isn't directed at children under 13, and we don't knowingly collect their data. If you believe a child has given us personal information, contact us and we'll delete it.

Changes

If we change this policy we'll update the date at the top, and — when the change is significant — tell you in the app before it takes effect.

Contact

Appentium · info@appentium.com · appentium.com (opens in a new tab)