Regarding an API to bypass Wi-Fi: I think at least on iOS, such a thing does not exist, and on Android I'd be extremely annoyed as well if an app were to possibly incur data and/or roaming charges for this. (I'm not sure whether there is an Android API to send only a specific request over mobile data without impacting other, already existing connections.)
Ah, that makes more sense.
> Regarding an API to bypass Wi-Fi: I think at least on iOS, such a thing does not exist, and on Android I'd be extremely annoyed as well if an app were to possibly incur data and/or roaming charges for this. (I'm not sure whether there is an Android API to send only a specific request over mobile data without impacting other, already existing connections.)
I believe the Andorid ConnectivityManager API allows this. I didn't realize iOS didn't have something similar, although there are probably good reasons not to want apps to be able to do this.
I think the intended method of using this API is to use apis from within a mobile app to make the request transparently (and ensure mobile data is used to avoid users having to manually disable wifi), but the person in the article is just generating a QR code that you have to scan so I assume you would indeed have to disable wifi by hand each time which would make it more trouble than its worth.
I had no idea mobile network operators were tacking on my phone number to requests though (presumably unsecure http only but still)...