New Fairphone 4 seeing poor mobile data performance.
Using a Smarty (3 UK) SIM. My wife’s Pixel 4a with identical SIM card will be on 4g while my FP4 is apparently stuck on H or H+.
Has anyone else seen this kind of issue?
Could it be a software issue or poor phone antenna?
Just to make sure I understand correctly:
Sorry yes I should have said it does select 4g but not as quickly as the Pixel 4a does.
Preferred network type is set to 5g/4g/3g/2g
To clarify it sometimes stays on H/H+ even though my wife’s Pixel 4a is on 4g.
Does it help to manually search for networks? It should list the operator as well as the available standard. You could then also try to manually connect to a 4G network if you find it. It is also possible that both devices use different frequency band and that the Pixel just works better with what your network operator uses in your area.
Smarty uses the UK Three mobile network. This uses LTE bands 3 and 20 for 4g which are supported on the FP4 as well as the Pixel 4a.
Just checked both phones side by side at home and the Pixel is happily connected to 4G whereas the FP4 was initially on 4g then dropped to 3G and stayed there.
It’s looking like a hardware/software issue with the FP4.
Tried to swap the SIM-cards?
No because the SIM now in the FP4 was in the Pixel 4a previously and it worked fine.
I see the same behaviour with the same configuration, SMARTY and Fairphone 4. It rarely goes to 4G. When there is 5G signal it does switch to 5G but I don’t have another 5G device to compare if the switch is timely. The majority of the time the phone is stuck at H/H+ or even get a blank mobile signal icon with a cross for the data (as if there’s no data connection at all). I also checked the bands that 3 is using and they seem to be supported by the Fairphone. Not sure if it is a provider coverage problem or a HW/SW problem with the phone.
SIM cards are fickel and may work better in soem phones than others due to the quality of the contacts.
Apart from tarnish which requires more friction
SIM card slots are made with parameters of width and height and no phone is exactly the same although a range of phones are likely to be.
Even a slight distortion of the SIM card or slackness can lead to poor contacts. Sometimes it can be ameliorated.
In the case of a tight fitting SIM that bends, usually due to a width issue the card can have the sides reduced.
In the case of the height being a big oversized then the SIM crad can be thickened with either temporarily with a piece of paper or the back coated with nail varvish.
NOTE They above are just ideas not directions or advice 
but trying alternative SIM cards etc. may be helpful ??
It would be interesting if anyone else has a comparison with a different provider (Vodafone, EE, O2).
I really don’t think the problem is with SMARTY (3 UK) as it’s perfectly fine in my wife’s Pixel 4a.
I think that unfortunately the antenna/radio system in the FP4 is just not as good as some other manufacturers. I wonder if this is somehow related to the FP4 being more modular for repairability?
I had also checked the cellular radio bands used by 3 UK and noted that the FP4 was compatible.
I have also noted that WiFi signals are also lower in the FP4 as opposed to the Pixel 4a.
I will upload a couple of screenshots from ‘Network Cell Info Lite’ app (which also shows WiFi as well as mobile cell data) once I’ve worked out how to do so 
Thanks for the information. Unfortunately don’t have any other SIM cards I can try.
A friend and if you are ‘lucky enough’ a micrometer to measure the SIM card etc.
An update on this, I have been roaming using the same phone and SIM card over the Christmas period to Greece, the phone has been happily connecting to the local networks using 4G, no drops to H/H+. I will look into the network bands that the Greek networks are using and report back if they are different from 3’s bands which I suspect is the case.
Sounds interesting. It might be worth raising this with Fairphone support especially if the frequency bands are different.
If you do decide to raise this topic with Fairphone support it might be worth referencing my issue which was logged as Request #560749.
Fairphone have closed my issue thanking me for the information and suggesting it will be taken into account for future development.
With the latest update to Android 12 the phone is mostly on 5G. So it seems that it was something happening at the OS/Drivers/network stack level. Not sure if other people noticed a difference after the update?
My FP4 on A11 has always been “mostly on 5G”, even when in the boonies, so there is definitely some Operator/Fairphone interaction (or lack thereof) going on here.
I’m curious to see what will happen when it finally upgrades to A12.
I have not seen any difference in behaviour since the Android 12 update.
There is no 5g where I’m located so cannot comment on that.
Did you ever look into the Greek frequency bands and compare them with SMARTY/3UK?
