How Folio Stand Sync Works
Folio Stand will sync your library between iPad and iPhone through your own iCloud, and it is designed so sync can never lose your music. Each score is identified by a fingerprint of the file, so the same piece cannot appear twice. If two devices change the same marks, you keep both. Every change sync makes can be undone for 30 days, and Stage Lock holds incoming changes while you perform.
Folio Stand is in development, with launch planned for early 2027. This page explains how sync is being built.
Why does sheet music sync go wrong?
Musicians who use two devices report the same few problems again and again, across many apps:
| What musicians report | The usual cause |
|---|---|
| The same score appears twice, or bookmarks multiply | Each device gives the same file a different ID |
| Marks or setlists vanish | One device overwrites the other ("newest change wins") |
| "It cannot be undone" | No history of what sync changed |
| An update breaks sync with an older device | The new version changes the data format |
| Sync silently stops | Uploads fail and nobody is told |
Folio Stand's sync is designed around each of these.
How Folio Stand sync works, in plain words
1. No duplicates, ever
When you import a PDF, Folio Stand takes a fingerprint of the file itself. That fingerprint becomes the score's ID. If you import the same PDF on your iPad and your iPhone, both devices give it the same ID, so it shows up once. The same goes for bookmarks and setlist entries.
2. Conflicts are kept as layers, not overwritten
If you mark up a page on your iPad while your iPhone is offline, and also mark it on the iPhone, Folio Stand does not pick a winner. It keeps both. The other device's marks appear as their own layer, named with the device and time (for example "Concert (from iPhone, 3 Oct 14:02)"), and a banner tells you. You can keep both, merge by hand, or hide one. For details like titles and tags, each field is merged on its own, so changing the composer on one device and a tag on another keeps both changes.
3. 30 days of undo
Every change that sync makes is written to a change log. For 30 days you can open "Undo sync" and roll back a change, score by score. Deleting a score on one device moves it to the trash on every device, and the trash keeps it for 30 days.
4. Stage Lock
While a setlist or Stage Mode is open, incoming changes wait. Your performance iPad cannot change in the middle of a gig because someone edited a part at home. When you leave Stage Mode, the waiting changes arrive.
5. A status dot on every score
Each score shows whether it is synced, waiting or has a problem. One Sync Status screen shows everything in plain words, with a "Copy diagnostics" button for support.
6. Your own iCloud, no accounts
Sync runs through Apple's CloudKit, in the private iCloud database of your own Apple Account. We run no servers that hold your music, you never create a Folio Stand account, and we cannot see your library. Your PDFs always stay downloaded on the device, so your music opens with no internet.
Sync is not a backup, so you also get backups
Sync keeps devices matching. Backups let you go back further. Folio Stand will keep automatic backups (7 daily and 4 weekly) in a folder you can see in the Files app, in an open format, and you can export your whole library at any time, free.
What if automatic sync is not ready on time?
We will not ship automatic sync until it passes our tests: two devices, airplane mode, an app killed halfway through an upload, a full iCloud, and a fresh install onto 2,000 scores. If those tests are not passing in time, Folio Stand will launch with a manual "Sync now" button that shows a preview of every change before it happens. It uses the same engine, so the promise stays the same: sync cannot lose your music. See the roadmap.
How does this compare with forScore sync?
forScore also syncs through iCloud. Its help pages say that when devices disagree the newest change wins, and that synced data "cannot be reverted or restored." Folio Stand keeps both versions of conflicting marks and keeps 30 days of undo. If you are fixing forScore sync today, see forScore sync not working.
Technical details (for the curious)
- Engine: Apple CloudKit with CKSyncEngine, in the user's private database. No third-party servers.
- Record IDs: a score's ID is a cryptographic hash (SHA-256) of the PDF bytes. Bookmarks, setlist entries and links use IDs made from their parent's ID plus their position and title, so a retried upload replaces itself instead of making a copy.
- Metadata merge: last writer wins, one field at a time, using a per-field modified date.
- Annotations: stored per page and per layer. Page IDs come from the score hash plus the original page number, so reordering pages never moves marks. Conflicting versions become a new layer. Strokes are never merged automatically and never thrown away.
- Deletes: synced as moves to a 30-day trash, never as hard deletes.
- History: a 30-day change log powers "Undo sync". Annotation versions are kept every time you save: all versions for 24 hours, one a day for 30 days, then one a week for 6 months.
- Schema: fields are only ever added, never renamed or removed, so a new app version cannot break an older device.
- Assets: PDFs stay downloaded on each device. iCloud is never the only copy.
- Stage Lock: incoming changes are queued while a performance session is open and applied when it ends.
FAQ
Do I need an account to sync? No. Sync uses your own Apple Account and iCloud. There is no Folio Stand account.
Can sync create duplicate scores? No. A score's ID is a fingerprint of the file, so the same PDF on two devices is the same score.
What happens if I mark the same page on two devices? You keep both. The second set of marks appears as its own layer, and you choose what to do with it.
Can I undo a sync change? Yes, for 30 days, score by score, from the Undo sync screen.
Does sync work offline? Your music is always on the device, so reading and marking work offline. Changes sync when you are back online.
Is sync free? Sync is part of Pro, planned at $49.99 a year or $7.99 a month with a 14-day free trial. Backups and full export are free. See pricing.
Sources: Folio Stand engineering plan (October 2026); forScore help pages on syncing and iCloud; US App Store reviews of forScore (2026); Apple CloudKit and CKSyncEngine documentation.