OnePlus
Restrict Apps to Wi-Fi Only or Mobile Data auf OnePlus
Apps on OxygenOS default to using whichever connection is available, mobile data or Wi-Fi. For data-heavy apps like streaming or cloud backup tools, that means your monthly allowance can disappear fast if the app switches to mobile data whenever your Wi-Fi signal drops, even briefly.
The per-app network setting fixes this by letting you pin a specific app to one connection type. It sits separately from the system-wide mobile data toggle, so you can leave mobile data enabled for messaging or maps while blocking it entirely for one bandwidth-heavy app.
To adjust it, go to Open the Settings ➔ Tap on Apps & notifications ➔ Tap on See all apps ➔ Choose an app ➔ Tap on Mobile data & Wi-Fi ➔ Turn on/off Disable Wi-Fi or Disable data usage.
Turning on Disable data usage means the app only works when you are connected to Wi-Fi. Turning on Disable Wi-Fi forces the app to rely on mobile data even when Wi-Fi is available, which is useful for apps that behave poorly on certain routers.
If an app then fails to load content or shows a no-connection error, check whether the wrong option got toggled first before assuming a server-side issue.