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★★★★★
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Version 1.1 New look, new tools, and your collection everywhere you go. Redesigned app — fresh visual identity using Seiko’s own navy, white card surfaces and serif model numbers. Cleaner, more considered, more like the watches it covers. iCloud sync — your owned watches, wishlist, collection logs and settings now follow you across all your devices automatically. No account needed beyond your existing iCloud. Collection logs — record every wear, service visit and accuracy check for each watch you own. Set reminders when a service is due. Home screen widget — see your most recently logged watch at a glance, with a tap that takes you straight to its log. Seiko serial decoder — enter any Seiko serial number to identify the year and factory it was made. Handy for pre-owned and vintage finds.
Watch Collection - 4R Caliber is the only Seiko reference you’ll need — and the one place to track the watches you own. The 4R Caliber covers 1,100+ current and past Seiko watches across nine collections, from King Seiko and Prospex to Presage, Astron and 5 Sports. Search by model number, browse by collection, or dig into the archive for past models going back to 2012. Every entry includes full specs, dial variations, regional releases and a note on the caliber inside. FOR YOUR COLLECTION • Mark watches as Owned or add them to your Wishlist • Log every wear session, service visit and accuracy check per watch • Set a service reminder so you never miss an interval • Record price paid, purchase location, serial number and condition • Add your own photo alongside the catalogue shot • Export your whole collection as a PDF — ready for insurance FOR RESEARCH • Compare any two watches spec-for-spec, side by side • Decode any Seiko serial number to find the production year and factory • See when a caliber was first introduced and what’s genuinely new • Get a wrist-fit estimate based on your wrist measurement • One-tap search to shop for any watch across the web EVERYWHERE YOU ARE • iCloud sync keeps your owned watches, wishlist, logs and settings in step across all your devices automatically — no account needed • Home screen widget shows your most recently logged watch, with a tap that opens its collection log Built by a Seiko collector in the UK. Free, with no ads, no subscriptions and no sign-in required. Available in English, German, French, Spanish, Italian, Portuguese, Dutch and Russian. The 4R Caliber is an independent app and is not affiliated with, endorsed by or sponsored by Seiko.