Google Drive is the sync back end for people who do not want to run or rent anything. Ledgable puts the same plain day files into a visible folder in your own Drive, and every device signed into that Google account reads and writes it.

Set it up

1. Settings › Sync › choose Google Drive.
2. Sign in with Google. The permission asked for is to files the app creates in your Drive, not your whole Drive.
3. Tap Sync now. A folder appears in My Drive with calendar/2026/09/… inside it, the same tree a WebDAV host would hold.
4. On each other device, sign in with the same Google account and pick Google Drive. The folder is found, not re-created.

What is the same as WebDAV

• The files. Open the folder in Drive on the web and you can read a day in a text editor.
• The merge. Two devices writing the same day converge to a union, whichever transport carried it.
• The side files: reading and listening positions, contacts, boards, bookmarks, local feeds, reply drafts.

What is different

• Sign-in expires now and then; the status line says so and Settings › Sync offers to sign in again. A WebDAV password does not expire.
• The library hub for books is WebDAV only. Books can still come from files, an OPDS catalog, or the Bookshelf’s own folder.
• Google can read the folder. If that matters to you, pick a WebDAV host you own.

Switching, or running both

Switching back ends moves nothing: the old files stay where they were, new syncs go to the new place. To move, run Sync now on the old back end, switch, run it again, and confirm the tree arrived. Running both is allowed, the same files in two places, but keep every device on the same choice or they will not see each other’s days.

Revoking

Sign out under Settings › Sync, or remove Ledgable under your Google account’s third-party access page. The folder stays in your Drive; it is yours.