[hdra]

I want to see the problem solved, but this feels like the wrong solution.

Reminds me of the time where I couldn't trust what the UI says about the audio of my desktop computer running Linux circa 2005

[williamscales]

Many apps will prompt before doing a large download over data. Spotify has separate settings for mobile data and Wi-Fi streaming quality. One could imagine a video app would prompt before streaming on mobile data. I'm pretty sure this is the solution—perhaps the Android or iPhone media framework itself could implement something that would warn people if app developers are often forgetting to add this feature?

[KozmoNau7]

Android even goes too far here. "Download waiting for wifi", for a 20MB download. I use more data than that simply by opening certain apps!

[js2]

You can disallow cellular data on a per-app basis on iOS, so you could for example disable it for just Netflix.

[mikeash]

I think they're close to a good solution but not quite there. A tri-state button, where it's on/on-but-disconnected/off might have done it, or at least some indicator that "off" doesn't mean off.

[Steko]

The correct solution is "always turn on wi-fi when I get home". The phone knows when this happens, you can set reminders around it.

[planb]

No, it does not if the Wifi Chipset is disabled, because it uses wifi for location services (GPS would use way too much battery). That's exactly the problem: The wifi chipset is used for much more than just connecting to the internet.

[mschuster91]

You can also use the GSM Cell ID for this purpose. Once the user marks his/her home, grab the IDs of the surrounding cell towers and use these as trigger.

[pgeorgi]

It's exactly what my phone does (Nexus 5X with Android 8), likely by listening to wifi passively ("which SSIDs are around?")

[Sephiroth87]

That doesn't sound like a disabled chipset...