Data Usage (native)

A native Windows app that keeps a permanent history of how much data each app on this PC uses. Windows already measures it (Settings → Network & Internet → Data usage) but keeps only a month or two, and a Windows reset erases even that. This app copies it out every hour into a database on another drive, so the history survives.

Built with WinUI 3 on .NET 10. A native port of the Data Usage Dashboard web app, sharing its design and its rules but no code. Local only: no network calls, no server, no account.

What it shows

• Overview: all-time, 30-day, 7-day and latest-day totals (up and down); the daily trend with the heaviest day and days well above trend; a six-month activity heat map (Expand for the full history); daily traffic by app; hour of day; an optional "one app vs everything else" split; and where it went
  • Wi-Fi against wired, and per network.
• By App: the top 10 as download/upload bars, and every app with its share. Apps with enough history open a detail page: daily usage, hour of day, by network, the programs merged into it, and the raw identities behind it.
• Sync Status: whether collection is actually running, the run history, and the two scheduled tasks as Windows reports them.

Range chips (7d / 30d / 90d / All) apply to every page.

Screenshots

Every page, top to bottom, on an invented history (datausage demo-data) - nobody's real usage.

Overview - totals, trend, activity, daily by app, hour of day, the split, where it went

Activity - the full history as a heat map, in 26-week blocks

By App - the top 10 as download/upload bars, and every app with its share

App detail - daily usage, hour of day, by network, merged programs, raw identities

Sync Status - last run, run history with errors, and both scheduled tasks

Install

Windows 10 (version 2004 or later) or Windows 11, x64.

From a release (nothing else to install): download DataUsage-<version>-win-x64.zip from Releases, extract it, and in that folder run:

powershell -ExecutionPolicy Bypass -File .\Install.ps1

From source: needs the .NET 10 SDK. In a clone:

powershell -ExecutionPolicy Bypass -File tools\Install.ps1

Either way it installs a self-contained build to %LOCALAPPDATA%\Programs\Data Usage, adds Data Usage to the Start menu and to Settings → Apps → Installed apps (and Control Panel's Programs and Features), sets the data folder (-DataDir, default D:\PersistentData\data-usage-native; with no D: drive the app asks on first run), and registers two scheduled tasks. Windows asks for administrator approval once, for the tasks.

Keep the data folder off the Windows drive, ideally in a folder a cloud client backs up: that is what makes the history survive a reset.

Uninstall from Installed apps, or Install.ps1 -Uninstall. Your history is never deleted.

After a Windows reset, reinstall with -DataDir pointing at the same folder. Everything collected before the reset is still there.

How collection works

• Data Usage Native Collector runs every 15 minutes, unelevated and without a window. It records which network the PC is on, and once an hour reads Windows' usage database (SRUM) into the history, then writes a consistent backup beside it.
• Data Usage Native Snapshot is the one step that needs Administrator: a shadow copy of the locked SRUM file. It runs only Windows' own cmd.exe and esentutl.exe, with arguments fixed when you approved the install. The collector starts it on demand; no prompt appears.

SRUM is read with Windows' own database engine (esent.dll), so no extra tools are needed.

Using it

• Zoom like a browser: Ctrl+Plus, Ctrl+Minus, Ctrl+mouse wheel, Ctrl+0 to reset (50 % to 200 %, remembered). Also in the settings menu.
• Sync now (top bar or tray) collects immediately.
• Tray: closing the window keeps the app in the notification area, with the latest day's traffic in its tooltip. Right-click it for Sync now, the options and Exit.
• Notifications when a collection fails or collection stalls (settings or tray).
• Start at login: settings menu or tray. It starts straight to the tray.
• Rename an app, or change its colour: the pencil beside its name (hover a table row). Pick a colour or type its hex code; "Default colour" goes back. Both are stored with the history.
• Light or dark: Settings > Theme, or follow Windows' setting.
• Click a Top 10 bar to open that app's page.
• Logos: in the same pencil menu choose Set logo…, or drop an image on the app's name. Files live in the data folder's logos\, named after the app (Bitwarden.svg); dropping files there works too.
• This PC… in the settings menu sets the name on the overview and which app, if any, is split out from everything else.

The app always opens maximised.

Why the total can differ from Windows

Windows' Data usage page shows one network at a time. The totals here cover every network, so they are higher whenever the PC has used more than one. The per-network rows under "Where it went" are the figures to compare.

Development

dotnet build DataUsageNative.slnx
dotnet test --project tests\DataUsage.Core.Tests\DataUsage.Core.Tests.csproj
dotnet run --project src\DataUsage.Cli -- stats           # totals and top apps
dotnet run --project src\DataUsage.Cli -- demo-data demo-data   # an invented history
& tools\Capture-Views.ps1 -Views 'overview=overview,0' -FullPage 1440

dotnet run --project src\DataUsage.Cli -- read-srum <snapshot> --csv <SrumECmd csv> checks the SRUM reader field by field against SrumECmd's output for the same file.

License

MIT. Geist is © Vercel, under the SIL Open Font License (src/DataUsage.App/Assets/Fonts/OFL.txt).