Your collection on the web
Browse app.getzukan.com without an account; sign in with the same account to add cards and see yours from any browser.
app.getzukan.com is the catalogue behind the app, on the web: every card, its price and its sources. It reads without an account. Adding a card to your collection, watching one, or opening your collection takes your Zukan account: the sign-in page comes at that moment, and you land back on the card with it done once you are signed in.
Sign in with the email address of your Zukan account: you receive a sign-in link, the same way the app does. Open it in the browser you asked from. Accounts created with Apple or Google sign in with the address attached to them. Once signed in, the catalogue marks the cards you own, shows your completion on each set and your totals on the account page.
From the web you can add a copy of a card, in the finish shown and near mint, and watch or unwatch it. Editing a line (its condition, the price paid, the language of the copy) and removing cards happen in the app. Whatever you add here is on your phone at its next sync.