While 4G and 4G LTE is much more available than it used to be, it still is not consistent no matter where you go. Also,a lot of companies will 'throttle' the data speed if you use over a certain amount.
So, it all depends on where you live. I live in the boonies, and my 4G speeds are not as good as my cable. They DO have separete devices that go through the 4G network that is not tied to a phone for being a hot spot, and I think those are more efficient on the use of batteries than phones.
So, it all depends on were you are, and how much data you actually use. I need the dependability of the cable verses what my 4G coverage right now, because i work via the internet from home, but it's getting close. The 4G network is always getting more robust, and once I retire, I won't need the reliability, or the amount of data I use today.
Also, I think wires are a bit more secure than wi-fi for security purposes.. even with vpn.
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