This is the 12315th most frequent Polish word.
mobilnego
"Mobilnego" means "mobile" or "portable" in English, typically referring to something that can move or be moved easily.
In this sentence, 'mobilnego' is an adjective describing the kind of internet, specifically 'mobile'.
Używam mobilnego internetu, aby surfować po sieci.
I use mobile internet to surf the web.
Here, 'mobilnego' describes the transmitter, emphasizing its capability to provide mobile connectivity.
Znajdź miejsce z dobrym sygnałem mobilnego nadajnika.
Find a place with a good signal from a mobile transmitter.
In this case, 'mobilnego' characterizes the phone as being mobile, which is here synonymous with cell or portable.