Background Uploads on iPhone

Switch apps freely

Once an upload is running, you can switch to another app, lock your phone, take a call, or check Messages. The upload continues in the background. iOS schedules the network work efficiently, so your battery isn't hammered while it runs.

Network drops resume on their own

If your phone drops Wi-Fi and switches to cellular, walks out of range of a router, or the connection blips for any reason, the upload pauses and resumes when the network is back. You don't have to restart anything. Already-uploaded chunks aren't re-sent.

Notifications when uploads finish

When an upload completes while you're in another app or with your phone locked, ZappFiles fires a local notification with the transfer title. Tap it to open the app and copy or share the link. If you're already in ZappFiles when the upload finishes, the notification is suppressed and the success screen shows directly instead.

Resuming after a force quit

If you force-quit ZappFiles mid-upload (swiping it off the app switcher), the upload pauses and persists its state to disk. Reopen the app and you'll see a resume banner at the top of the Upload tab. Tap Resume and the transfer picks up from the last completed chunk.

The resume window is up to 7 days, after which the underlying multipart upload expires and the transfer can't be continued. For most uploads you'll never see this; for very large long-running uploads, finish them within a week.

What can interrupt an upload

Two things stop an upload outright: deleting one of the source files while the upload is running, or modifying its contents. ZappFiles checks file size and modification date when resuming and refuses to continue if either has changed, since otherwise the recipient would get a corrupted file. If that happens, restart the upload from the new version.

Cancelling

The progress screen has a Cancel button. Tap it to stop the upload immediately and clear any partial data on the server. There's no charge for cancelled uploads.