Working offline

Manga Vault works without an internet connection. Most features are available offline, with full sync resuming when you reconnect.

What works offline

Browsing your Library — Your full collection, including cover art (cached after first viewing).
Adding volumes — Scanning, manual entry, requesting (queued for sync).
Reading progress tracking — Mark as Reading, log pages, mark Completed. All local.
Shelves — Create, edit, delete shelves; assign volumes to them.
Filtering, sorting, searching — All Library operations are local.
Manga detail pages — Tap any owned volume to see its details (already cached).
Settings and preferences — Change theme, dark mode, etc.

What doesn’t work offline

Cloud sync — Pending changes queue up; nothing syncs until you reconnect.
Searching the broader catalog (Browse tab) — Limited to what’s already in your local catalog cache.
Friend interactions — Adding friends, viewing friend profiles, comparison data.
Push notifications — None received until reconnected.
Cover art for new volumes — If a volume’s cover hasn’t been cached locally, you’ll see a placeholder until you have a connection.

What happens when you make changes offline

Every change is stored locally as a pending change:

A note marker in the Sync Status (if visible).
The change applies to your local view immediately.
The change is saved to your phone’s storage (durable — survives app restart).

When you reconnect, all pending changes sync to the cloud. Order is preserved (changes apply in the order you made them).

What if I’m offline for days?

That’s fine. Pending changes accumulate. When you reconnect:

All changes sync (in order).
Catalog updates pull down.
Friend data refreshes.

A long offline period might result in a longer-than-usual first sync, but it’ll catch up.

Conflict scenarios

If you’ve been offline and made a change on Device A, while online on Device B you make a different change to the same volume:

The most recent change (by timestamp) generally wins.
For shelves, both changes are merged (union semantics).
Deletions take precedence (a deleted volume stays deleted).

This rarely causes issues in practice unless you’re heavily using two devices simultaneously.

How to know if you’re offline

Pull-to-refresh fails or shows a network error.
Friend profiles say “Unable to load.”
Search in Browse tab shows no new results beyond your cache.

Manga Vault doesn’t show a persistent “Offline” indicator — we don’t want to be alarmist. Instead, we just keep working and queue changes.

Battery and data usage

Sync uses minimal data when there are no pending changes. When changes are queued and you reconnect, sync runs and uses bandwidth proportional to the changes.

In airplane mode or limited connectivity:

App opens fast (no sync wait).
All your data is accessible.
New scans queue to sync later.

Tips for offline use

Pre-cache cover art. Browse your collection in grid view while online to ensure covers are cached.
Pre-sync before traveling. Open the app, pull-to-refresh, and let everything sync before you fly or go off-grid.
Don’t worry. Manga Vault is designed to be fully offline-capable.

Sync resumes automatically

There’s no “go online” button. As soon as your device gets a connection, Manga Vault detects it and starts syncing pending changes. You don’t need to do anything.