Choose Diarium for one-time platform purchases and sync through your own cloud account. Choose Day One for browser writing, shared journals, printed books and optional AI reflection. Both cover desktop and mobile journaling; payment, sync and moving your archive are the bigger differences.
This comparison of documented features is published by memoir, a journaling app developer. Our recommendations are editorial judgments, not a hands-on ranking.
Which should you choose?
Choose Day One if…
You want a dedicated journal with web access, optional guided AI tools and established book-printing and export workflows.
Choose Diarium if…
You prefer your own cloud storage and paying once for Pro on each platform you use. Native desktop and mobile apps cover your routine.
| Your decision | Day One | Diarium |
|---|---|---|
| Access | Mobile, desktop and web; features vary by platform. | Windows, Android, iOS and macOS native apps. |
| Paid plans | Silver and Gold annual plans. | One-time Pro purchase per platform; paid Windows app includes Pro. |
| Sync | Day One Sync; multiple-device access is in paid plans. | Optional Pro sync using OneDrive, Google Drive, Dropbox, iCloud or WebDAV. |
| Export decision | PDF, JSON, text and CSV availability depends on platform. | Restorable database backup is separate from document export. |
Sources: Day One plans, Day One export formats by platform, Diarium Pro FAQ and Diarium sync FAQ.
Writing and media: what the free versions include
Both apps accommodate writing with media. Day One’s free Basic plan permits one photo per entry; audio, transcription, drawing and expanded media are in paid plans. Diarium also reserves unlimited attachments and certain integrations for Pro. Day One plans; Diarium Pro FAQ.
For your trial, use the same photo and a few sentences. Notice how the editor handles adding a second thought later. That small routine is more useful to evaluate than an elaborate entry you would rarely make.
Writing an entry in each app. These images show different sample entries and device views; they illustrate the controls, not the results of an identical test.
Revisiting: visual browsing or guided AI
Both products have ways to revisit past dates and browse a journal visually. Day One’s illustrated timeline separates List, Calendar, Media and Map; Diarium offers timeline, calendar, gallery and map views. Day One features; Diarium features.
Day One also documents optional AI reflection tools. For server-based AI, relevant journal content is temporarily decrypted on the device and transmitted for processing after consent; this is separate from encrypted journal sync. Read the AI processing explanation if this is part of your reason to choose it.
Search: on your phone and computer
Day One supports text search and filters, with different controls across platforms. Its web and Windows interfaces offer filters for items such as tags, places and weather. Diarium describes keyword/tag search and date/location browsing. Day One search guide; Diarium features.
Cost: subscription or a purchase for each platform?
US dollars, checked September 13, 2026. Storefronts, taxes and offers can change the checkout price. Monthly and annual figures below describe their actual billing period, not an estimated monthly equivalent.
| Plan decision | Day One | Diarium |
|---|---|---|
| Published price | Basic $0. Silver $8.99/month or $49.99/year; Gold $74.99/year. US App Store; plan terms. | Pro $14.99 once for iOS and $14.99 once for macOS. Separate platforms: $29.98 for both. iOS store; Mac store. |
| Sync across both devices | Silver or Gold subscription. | Pro on each platform, using your own supported cloud account. Cloud-provider storage limits still apply. |
For iPhone and Mac writing with sync, Diarium’s two Pro purchases total $29.98 once at these prices. Day One Silver is $49.99 each year and includes a different bundle of services. Windows and Android prices are separate and are not included in this example.
Can you move an existing Day One journal?
Diarium lists Day One among supported imports. Day One’s JSON export can include media, while PDF serves a different, readable-copy purpose. Export a small sample first and inspect dates, photos and recordings after import. We have not performed an end-to-end migration test for this comparison. Diarium import guidance; Day One export formats by platform.
If Day One’s main appeal is everyday iPhone capture, the memoir vs Day One comparison explains another option, including its narrower platform support and backup limitations.
Sources and how we compared
Official documentation checked September 13, 2026. Images are identified in their captions. We have not tested comparative speed, reliability, security or a complete migration. Editorial policy.