When using the USB cable method, the phone is charging all the time through the USB port, so the battery will not be exhausted, ever, never ever, neverneverever.

If you set up the phone as a wifi hotspot instead, then yes it will eat battery power quite fast... unless you simply connect the phone to a charger while it is acting as a wifi hotspot. Problem solved.

I used to have such "USB SIM stick", and I didn't see any benefit with it, It didn't "work better", as in giving better speeds or anything, than using the same SIM on a phone.

The main drawback with it is (was) that in practice it needed its own SIM, unless you keep swapping the SIM between the phone and that USB SIM stick all the time, which will be a real pain in the butt. Then if the SIM is in the USB stick, you can't receive or make calls with your phone, as you could if the SIM was in it (yes, making and receiving calls even while that phone is providing internet connection to your laptop, works fine, I've done that all the time,, even played Team Fortress 2 while talking to my wife on that same phone).

I still don't quite understand why so many people try their best to make it look like a bad idea to use your phone (and its SIM) to provide internet for your PC/laptop. The issues raised in these discussions are either no issues at all, or rather insignificant (like the point that using and charging your phone a lot wears its battery... well, that's the nature of the beast, and as said I haven't seen my wife's phones lasting any longer than my phones, where the latter ones are often used for PC internet connectivity).

Just do it. It works, it is great, it is beautiful. Don't believe the naysayers.

I also usually use the USB method, just because then the phone charges all the time and it just feels simpler and more foolproof.

But the wifi hotspot method works fine too, as far as I can tell even the speeds and ping times are just as good as with using an USB cable. I'd use the wifi hotspot method mainly if there are several devices which would want to use the phone for internet connectivity, at the same time.

I was thinking more about taking the phone away, maybe to some part of the house "far" from the computer, or just take it with you when you go out. (In which case you would need another SIM card for your USB modem or hotspot, but that's what I did anyway.)

Also, I wouldn't want to be downloading some big file and have a half-second disconnection on incoming calls.

But ok, not the biggest problem, to "use the phone as a phone". For me what's a bigger problem is...

Mainly the battery. You're right that the phone will not break down because of prolonged and intensive use, at least will not break down noticeably faster than a less used phone, but the battery will. Again, not because of the intense use, but because you're just going to have to recharge it more often, and battery life is measured in charge cycles.

Now if you're going to replace your phone every 2 years, there's nothing to argue, go ahead. A "modern" battery should last those 600-800 charge cycles. But I replaced my last phone after 6 years and I expect my current one to last other 5-6 years... except the battery, which I had to replace after 3-4 years.

All things considered, I would still get a 30-40 euro device to act as a modem and keep my phone for regular use, unless the cost of a second data plan was too high.

That completely depends on the ISP/country.

Here in Finland you can get a 4G/LTE SIM with unlimited data plan for like 18€/month, where the speeds can reach up to over 100Mbps(*) depending where you are and how congested the network is. I've used such to download hundreds of gigabbytes, and the ISP here has been cool with it (because they have no choice, as the competition between ISPs/telecom operators works fine here, and the customer is the king).

(*) At least with Telia SIM; I know that e.g. the DNA telecom operator here likes to limit the highest speed to around 50Mbps, not sure if Elisa (the third ISP/telecom operator) has similar upper limit in place. Anyways, even that "limited" 50Mbps would be fine to me.

I guess I could test it, but I don't think that aborts the download or anything. It just means there is a half a second pause with the download, and then it proceeds normally, as if there had been a slight hiccup/slowdown in the internet connection.

At least when I was playing Team Fortress 2 over the phone and I got an incoming call, there was just this short pause/lag in the game just before the phone rang, but right after that the game went back to normal. I wasn't disconnected from the game server or anything.

Fair enough, but as said, I haven't noticed much of difference between my and my wife's phones, when it comes to the battery wearing out. My phone(s) are often used for internet connectivity (usually with an USB cable, which means the phone is charging all the time then), while my wife's phone never is. Then again, she does use the phone quite a lot otherwise, for Facebook and calling her friends, so even without internet sharing, it is under quite a lot of use.

Also, usually we want to change the phones for other reasons already before the battery dies out. For my wife it is usually that she has this magical capability of destroying the glass so often (her current phone has a crack on the glass as well). For my phones the reason quite often is that it is in the news that Android phones have some severe vulnerability problem, and I realize I haven't received security updates for my old phone for a long time.

It also helps that I tend to buy cheaper 100-150 € phones, I just don't see the need for more expensive phones. Like this Samsung Galaxy J5 (2016) phone that I have right now, I've been completely happy with it, using it also as a car navigator, browsing the web with it etc. I think I paid around 120€ for it, and the best part is that it has a detachable/replaceable battery. Now I am getting a more expensive phone from my employer though (Honor 10 64GB, costs here something like 400€ or so, fine as I don't have to pay for it).

The reason I don't like that setup is that it needs another SIM, which at least here quite often seems to mean double monthly costs. So instead of having one SIM for 20€/month, I'd need to have two SIMs for 40€/month. one for the phone and another for the USB SIM stick. The extra cost adds up quickly, with that extra cost you could buy a new phone with a fresh battery every year.

There may be some ISPs who don't charge twice as much for an extra data SIM.

Hi timppu

many thanks for your detailed responses, I will definitely be trying this out.

Not really much else I can do, over here the other main ISPs all jump on the bandwagon when one announces a price hike.

10% increases are not justifiable in my opinion so it's the smartphone route for me, thanks again.

Ask them if they have some kind of bundle offer though. Here some ISPs have had such that you get a mobile data SIM + USB SIM stick with the bundle, but if I recall right usually it is bundled when you buy a fixed line internet connection from them, not like you get a normal SIM (which has a data plan), and on top of it also a "free" data SIM for mobile use.

Also when getting the SIM, ask them these questions, if they are still unclear:

- Is there a monthly data transfer cap or is it unlimited (within reason)?

- If it is capped, what happens when the monthly limit is reached? Is the data transfer speed slowed down for the rest of the month, or do they start billing extra charges for the extra data?

- Is there some kind of upper transfer speed limit, e.g. 10Mbit/s or 50Mbit/s, or is it as fast as the network allows? Like I said, the fastest I've seen with my 4G/LTE SIM was around 124Mbit/s at one time, which was nice.