Which app used all my data? Top bandwidth users in Pulse

When your broadband allowance runs out early, or the connection crawled all evening, the question is always the same: what used it? Pulse by Zaweba answers it with a list on the History page that ranks your apps by the network data they used over a period you choose.

Where to find it

Open the History page from the View menu, with Ctrl+3, or from the tray menu. At the top is a Show selector with three choices: Today, Yesterday and This week. Pick one, and the top bandwidth users list ranks apps by how much network data each used in that time, biggest first.

Above the lists you'll find a network graph for the same period and totals, so you can see when the heavy use happened as well as who was responsible.

How it knows

Pulse records a one-minute history in a local file on your PC, and network use for each busy app is part of every minute. It also stores Windows' own hourly per-app data-usage records. That second source matters, because it means the list works even if you haven't turned on live per-app network counting in Settings. You get a useful answer from the first day, whatever mode Pulse is in.

Nothing is sent anywhere. The history stays in Pulse's folder in your user profile, and you can choose in Settings, History how many days to keep, from 1 to 365, with 30 as the default.

Making sense of the list

The top of the list usually holds no surprises: a streaming app after a film, a game launcher after an update, a cloud storage tool after you added photos. The useful part is spotting the one you didn't expect. A program you barely use near the top of This week deserves a closer look.

Switch between Today and Yesterday to see whether something is a habit or a one-off. An app that appears high every day is probably syncing or updating on its own. One that appears once was likely a single big download.

Then look at the network graph for the same period. A long, flat block of heavy use overnight points at a scheduled backup or update. Short, sharp peaks during the day match things you were doing yourself.

Doing something about it

Once you know the app, go to the Live page, type its name in the Find box, and select it. Open file location tells you where it lives if the name isn't clear. Most heavy users have their own settings for when and how much they download, and changing those is usually the better fix than closing them.

If you're on a capped or metered connection, set up the daily data per app alert on the Alerts page. It warns you when any single app passes a set number of gigabytes in a day, so you hear about the problem while it's happening rather than at the end of the month.

Things to keep in mind

Windows' own usage records are grouped coarsely, by the hour, so treat the totals as a good guide rather than a meter reading from your provider. They're excellent for finding the culprit, which is what the list is for.

And remember that This week only reaches back as far as your history does. If you've just installed Pulse by Zaweba, the list fills up from that moment on.