Why a big upload on mobile data keeps starting over

If you export from a phone on mobile data, you may have watched a progress bar climb a little, drop to zero, and climb again. It feels like the render is failing. Usually the render has not even started: that part of the bar is your video going up to the server.

What goes wrong

Large files are uploaded in parts, so that one bad moment does not lose everything. On a moving phone connection, parts fail often. A simple uploader counts a failed part as lost progress, so the bar falls back, and after a few failures it gives up and deletes what it had. The next attempt really does start from zero.

We had exactly this bug. It hit phones on Indian mobile networks far more than anyone else, because that is where parts fail.

What Captik does now

• The bar only moves forward, and a chip tells you when it is reconnecting or waiting for a network
• A dropped upload is kept. Press Export again and it sends only the missing parts, and tells you how much of your video is already saved
• A finished upload is remembered, so exporting the same file again does not upload it twice
• Phones use smaller parts, and the number sent at once steps down when the network struggles

What helps on your side

1. 1Keep the tab open and the screen on until the upload finishes, because a phone can suspend a tab in the background
2. 2Try again within a day. Unfinished uploads are cleared after about a day, so a much later retry starts over
3. 3If a clip is very large and the network is poor, use WiFi for the upload, or trim the clip first
4. 4Use the Smaller file option when the export itself is what you need to send on

A failed export gives its export minutes back. A slow upload costs you time, not minutes.