Privacy policy

Last updated 16 October 2026

Who is responsible

Edison Companion is made by an independent developer. For any privacy question, write to support@edisoncompanion.com.

What stays on your phone

• Your collection, decks, siding plans, wishlist and settings, unless you sign in to an account (see the next section).
• The corrections you make when importing a screenshot, which the app uses to recognise cards better next time.
• Card pictures and prices you have saved.
• Screenshots. They are read on your phone and are not uploaded anywhere.
• Diagnostics. If the option is on (Settings → Screenshot import), the app keeps a text log of how an import went, and optionally a copy of the last screenshot. These stay on your phone unless you choose to share them, for example in an email to us. You can turn this off or clear it at any time.
• Backups. A backup is a file you save yourself. The app does not send it anywhere.

Your account (optional)

You can create an account with an email address and a password in Settings → Account & sync. If you never do, nothing in this section applies to you.

What we store when you have an account:

• Your email address.
• Your password, as a one-way hash kept by our sign-in provider. We cannot read it.
• Once you sign in on a device: a copy of your collection, decks (their cards, siding plans and tags), wishlist, and a few display settings, so they can be restored and kept the same on your devices and on our website.

What is never uploaded: screenshots, the corrections the app learns from your imports, Duel background photos, and saved price and picture data. They stay on your phone.

How it is used: only to run your account and sync. We do not read your collection for any other purpose, do not use it for advertising, and do not sell or share it. It is stored on this app's own server (Supabase), where each account can reach only its own rows. We send you email only when you ask for it: to confirm your address and to send a password reset code.

Deleting your account: in the app, go to Settings → Account & sync → Delete my account. That removes your account and everything synced to it from our server straight away. Your data on your phone is not touched. If you cannot open the app, see how to delete your account.

Signing out stops syncing and keeps the data on that phone. If you use “Delete all my data” while signed in, the app asks whether to erase this phone only or the phone and your account.

What the app connects to

When you use these features, your phone contacts the services below directly. They can see your IP address and the request, as with any web request. We do not receive that information, and each service has its own privacy policy.

Service	Why	When
Cardmarket (downloads.s3.cardmarket.com)	Downloads its public price file	When you tap “Update prices”, or automatically while you use the app (this download happens only over Wi-Fi)
YGOPRODeck (db.ygoprodeck.com)	Cheapest-printing prices	Same as above
This app's own server (Supabase, aoslkdxvfyidmruqtikv.supabase.co)	Card pictures (mirrored from YGOPRODeck onto our own storage, so your phone never has to contact YGOPRODeck's image server directly), a public file of US card prices (a copy of TCGplayer's market prices, refreshed by us a couple of times a day), and TopDeck.gg tournament data without an API key ever shipping inside the app	Loading or saving pictures, refreshing US prices (automatically, about once a day while you use the app, or when you tap Update), or using Import from TopDeck.gg
This app's own server (Supabase)	Creating an account, signing in, sending the email codes, and syncing the data described above	Only if you create an account and sign in
TCGplayer, Cardmarket, eBay, edisonformat.net	Websites you open from a link in the app	Only when you tap the link

When you use Import from TopDeck.gg, your search is relayed through our own server (above) to TopDeck.gg — your phone does not contact topdeck.gg directly, and TopDeck.gg does not see your IP address. Our server, like any server, can see standard request logs (such as IP address and what was requested) for the pictures and TopDeck.gg lookups it relays; we do not use this for anything beyond running the service and keeping it working.

If you choose “Load pictures from the web: off” in Settings, the app does not load pictures from the internet at all.

Permissions

• Photos: to let you choose a screenshot to import. The app only reads the photo you pick.
• Camera: to scan a card’s passcode. Nothing is saved or sent.
• Save to photos: only if you choose to save a deck image to your photo library. The app writes that one image and does not read your other photos.
• Notifications (Android): to show a notice while a duel keeps running in the background. They are shown on your phone only; nothing is sent anywhere.

What we do not do

• We do not collect your name, location or device identifiers in the app. We collect your email address only if you create an account.
• We do not use advertising or analytics services in the app.
• We do not sell or share personal data. If you have an account, your email and synced data are used only to run the account and sync.

This website

This website does not use cookies or tracking scripts. It is hosted by Cloudflare, which processes standard server logs (such as IP address and pages requested) to deliver and protect the site.

Buy links

Some buy links may be affiliate links, meaning the developer may earn a small commission if you buy after following one, at no extra cost to you. When links are affiliate links, the app says so next to them. Following a link takes you to the store’s own website and its own privacy policy.

Children

Accounts are for people aged 13 and over. Without an account the app collects no personal information from anyone, including children. It is a general-audience app.

Your choices

• Delete your data from your phone at any time in Settings → Storage → “Delete all my data” (if you are signed in you choose this phone only, or the phone and your account), or by uninstalling the app.
• Delete your account and everything synced to it in Settings → Account & sync → Delete my account, or see how to delete your account.
• Clear diagnostics, reset learned corrections, and remove saved pictures in Settings.
• Backups you have saved stay wherever you saved them until you delete them.

Changes

If this policy changes, the date above will change, and the app’s About screen will point to the current version.