Using old phone (S8+) instead of a 4g router?

I am about to get a new phone and am wondering if there are any downsides to simply using my old S8+ (which I believe is a cat16 LTE) for my home broadband rather than getting a full blown 4g router. I believe I can simply tether my phone to my Asus AC86U (merlin) to provide the wan access to the asus via usb, all my devices connect to the asus so effectively my setup is identical except the wan comes from the usb instead of the old FTTC phone line.

What I am not sure about is if there are any down sides to this setup vs using a 4g router? I can get maybe £120 for the phone if I trade it in, a 4g router is going to cost more than that (a lot more if I get a cat16 one vs the usual cat6 most seem to be). So it will work out cheaper provided there are no drawbacks to doing this. It also means I am not buying a 4g router which will be obsolete as soon as I get 5g here (which might be soon as there is a fair bit of coverage around me, just not at this location yet).

I get 50-55mb at most via my FTTC with an 8ms ping, I can get 120-140mb over 4g on this phone with a 15ms ping (seems pretty consistent in all my tests day and night). The FTTC is costing £50/month including a phone line which I don't need. I can get the sim cheaper than that and more than double my speeds at the same time and it seems all I lose is 7ms of ping.

Can the phone be powered with only the power cable plugged in (no battery). No harm in using the phone, but I wouldn't want to be charging a battery all day every day. That's not to say batteries can't cope - many people with laptops do the very same thing. However the amount of heat the phone will be producing whilst tethering could be damaging to the phone and certainly the battery.

Connecting my "better/newer" phone (Huawei P10 Lite) via USB to my bog standard ASUS RT-N66U worked fine for me. But being my active phone that was inconvenient, as the router is upstairs. So I very quickly ended up just using the phone as a mobile hotspot, supplying up to two laptops and an iPad.

It still of course worked perfectly well as a phone when supplying the other kit. The drawback as a hotspot was that it drained the battery and got rather warm. I largely solved the first of those by plugging it into a powered USB port of my main laptop.

My "older" case-damaged phone (Galaxy SIII) also worked plugged into the ASUS but doesn't have as oomph and would have needed an unlimited SIM itself. So that was a no-no solution.

The method fell down when I installed wireless security cameras and cloud storage for them. (I regard home recording from them as rather pointless). My phone of course left the premises when I did! So I got the Three HomeFi. Unfortunately while the older B311 was supplied but it suffices.

Net saving of dropping FTTC; landline and replacing my low end EE mobile service with the £20 Three Unlimited SIM was initially £69pm. Reduced to £47 when I got the HomeFi. Another plus is I now have unlimited data on my phone instead of 500MB. I didn't realise how much benefit that gives by removing all concerns about it.

You must have posted that just as I started drafting my reply to the OP. I did worry quite a bit about the heating. The phone did get quite hot at times.

I didn't keep it continually on charge once I changed from plugging into the ASUS to laptop USB, because that too was a bit inconvenient and clumsy. For a bit I tended to keep it stand-alone then top up with its own fast charger when low. A problem that won't apply to the OP, but might to others considering the same types of usage. All solved of course by getting the HomeFi.

I wonder if a straight dongle would work better than a phone for the OP's purpose?

In reply to a post by RobertoS:

I wonder if a straight dongle would work better than a phone for the OP's purpose?

Most of the dongles are quite low specification, Cat 3 at best in my experience. Okay for a laptop that is on the go, but really rubbish compared to a Cat 16 phone.

However one of these might work, without battery:
https://www.amazon.co.uk/NETGEAR-AC810-100EUS-Broadb...

I was looking at that neatgear earlier. If it was future proofed with 5g (and could handle mmwave in future) it would be a no brainer. EE coverage checker literally shows a 5g signal at the other end of the road which must be less than 400m away. I don't know how accurate that is, perhaps I can even get a 5g signal already (won't know until new phone arrives), but I would hope even if I can't get a signal now, it won't be too long before I can. So the bigger question might be when can I get a future-proofed 5g router for a reasonable price.

Thanks James . I didn't know that, and these days many people could presumably use their phone "on the go" as I do if I need my laptop or iPad for some reason.

Yes, I know because I have a dongle from work, for my work laptop!

Edited by jchamier (Sun 16-Feb-20 13:58:11)

In reply to a post by Ewok:

So the bigger question might be when can I get a future-proofed 5g router for a reasonable price.

I think we will both be waiting:
https://www.netgear.com/home/products/mobile-broadba...

Not yet on sale

In reply to a post by jchamier:

In reply to a post by Ewok:

So the bigger question might be when can I get a future-proofed 5g router for a reasonable price.

I think we will both be waiting:
https://www.netgear.com/home/products/mobile-broadba...

Not yet on sale

Oooh now that's what I need! cat22 for 4g as well unfortunately release date is "second half of 2020" so a long wait!

Skeptical about the signal it will get though, it doesn't even have any antennas, they gotta provide better signal than ones purely inside the box itself? It's clearly designed primarily as a portable device hence the battery, even though it can obviously be used as a home device as well, I wonder if something with antennas external to the box would provide better reception.

Edited by Ewok (Sun 16-Feb-20 16:29:21)

In reply to a post by Ewok:

Skeptical about the signal it will get though, it doesn't even have any antennas, they gotta provide better signal than ones purely inside the box itself? It's clearly designed primarily as a portable device hence the battery, even though it can obviously be used as a home device as well, I wonder if something with antennas external to the box would provide better reception.

The older device (Netgear 810) has SMA connectors. No idea about this new N5.

There is the N1:
https://www.amazon.co.uk/NETGEAR-MR1100-100EUS-Night...

and N2:
https://www.amazon.co.uk/NETGEAR-MR1100-100EUS-Night...

Which might have SMA connectors?