national roaming priority tool?
I am with gsm carrier who uses national roaming for his services. There are 4 carriers for calls but the internet services are availiable onle when the phone is connected to one of them. This internet services carrier has good signal in cities but almost no signal in the countryside. However, the other carriers have stronger signal usually. So the effect is that the phone connects usually to no-internet carriers, even in the cities. I have to change carrier manually to internet carrier but this is not a solution as I have to manually reconnect to calls carriers when outside of the city.
So my question is if there is a way (tool) to prioritize carriers or in other words to set rules for the phone on how to choose services carrier?