Question about Digitec iot Data Flat

I have equipped my retrofitted car sat nav with it. 35MB app download takes half an hour. You can navigate with a little patience.

And the speed is not suitable for surfing, at most WhatsApp without pictures or videos. The plan is only intended for devices that require an internet connection for data exchange, and only if the amount of data is rather low. (e.g. smart wallbox, robotic lawnmower)

The plan is for data only, no telephony.