codes. is a promo code and voucher manager for businesses. This page explains what data the app handles, where it is kept, what our server can and cannot see, and how to delete it.
The app is published by EVDiag, the data controller for the limited data described here. Contact: support@evdiag.net.
The app keeps the following in its private storage on your device:
Android system backup of the app is switched off, so this data is not copied to Google's cloud backup. If you export a backup file (Settings → Data & backup), you choose where it goes; it is your copy and we never receive it.
Phones in the same team (one Owner and the Distributors they pair) exchange code transfers, status reports, redemptions and permission changes through our relay server, which runs on Cloudflare Workers. Pairing itself happens by scanning a QR code; the team key travels in that QR code from phone to phone and never through the server.
Everything a phone sends is encrypted on the device with AES-256-GCM using the team key before it leaves. The relay stores and handles only the following:
The relay never sees your codes, vouchers, customer or partner details, member names, or anything else inside the encrypted packages.
Paid upgrades are bought through the Apple App Store or Google Play. We use RevenueCat to check purchases. RevenueCat receives an anonymous app user identifier and the purchase receipt; Apple or Google handle payment and never share your card details with us. When an Owner's team is created, the app sends that anonymous RevenueCat identifier to our relay so it can confirm which team size the purchase allows. See RevenueCat's privacy policy.
Crash reporting is off until you turn it on in Settings. When it is on and something goes wrong, the app sends a short report to our relay: the error message and technical stack trace, app version, platform, which screen was open, a random install identifier and the time. Before sending, the app strips code-like strings and email addresses from the text. The relay does not store reports; it forwards them to a private developer notification channel (a Discord or Slack webhook) so we can fix the problem. Turn the setting off and no further reports are sent.
If you send a voucher to a customer through WhatsApp, email or the share sheet, or export a file, the content goes to the app or person you choose. That transfer is between you and that service; we are not part of it.
If you use the form on our support page, the name, email address, topic, optional device details and message you type are sent through our relay to Resend, which delivers them as an email to support@evdiag.net. The relay does not store them. We keep the email only as long as needed to answer you and use your address only to reply.
We do not sell or rent data, and we do not share it with anyone for advertising.
Your business data lives on your device. To remove it, use Settings → Danger zone → Clear all data, or uninstall the app.
To remove your data from our server, use Settings → Danger zone → "Delete my account". This erases your member record, any messages queued for you and your encrypted recovery backup, then clears the phone. If you are the team Owner, the whole team is removed from the server: every member record, queued message, backup and redemption log. You can also ask us by email at support@evdiag.net — useful if you no longer have the phone. See also How do I delete my online sync data?
When an Owner removes a Distributor from the team, that Distributor's member record, queued messages and recovery backup are removed from the server as well. Queued messages are deleted on delivery or expire after at most 30 days.
Team data is encrypted end to end with AES-256-GCM and a fresh random value for every message. The team key is created on the Owner's phone and passed to Distributors by QR code only. Each phone signs in to the relay with its own key pair and session tokens; the server stores only hashes of tokens and Recovery Codes. All connections use HTTPS / secure WebSockets.
Your Recovery Code can restore your place in the team and your team data — treat it like a password and keep it private.
Depending on where you live (for example under the EU/UK GDPR), you can ask to access, correct, export or delete personal data we hold, object to processing, or complain to your data protection authority. Because the server holds only random identifiers and encrypted data, the in-app "Delete my account" covers almost every request. For anything else, email support@evdiag.net. We process the limited server data to provide the service you asked for (team sync, recovery and purchase checks) and, for crash reports, on the basis of your consent, which you can withdraw in Settings.
Some of these providers process data outside your country, including in the United States, under their standard data protection terms.
The app is meant for businesses and adults distributing promotional content. It is not directed at children under 16, and we do not knowingly collect data from children.
If we change how the app handles data, we will update this page and its "Last updated" date. Significant changes will also be announced in the app.
Questions about privacy: support@evdiag.net