Recently, I’ve bought a slightly used iPhone 15 model, but it was imported from the US (so it’s an eSIM-only model). I live in Poland and use Play! carrier, which has good 5G coverage in my area. However, my 5G speed never gets over 60-70 Mbps, and when I switch to LTE, there’s no speed difference.
My wife has an iPhone 13 Pro (3uTools reports it as for the Japanese market, even though it was bought in Ukraine) with a physical SIM from the same carrier. She gets around 600-700 Mbps 5G speed in the same area.
What could be wrong with my iPhone? I have already tried playing with cellular settings, resetting network settings, etc. Could it be due to restoring a backup from my previous iPhone (XR)? Or could there be some hidden settings in the device causing this? The spec sheet says that US iPhone 15 models support all cellular bands used in Poland.
P.S. Both my wife and I use dual SIM setups due to Ukrainian eSIMs, so that shouldn’t be the reason for this behavior. Both iPhones are running iOS 18.2.1.
It’s a common problem with international phones. There are all kinds of Android phones I wish we could use here, but the bands don’t support them. Vice versa with US phones outside the US.
Small favor to ask: Check/compare your modem firmware and carrier profiles version. Sometimes different devices like to ‘hang’ on different bands, which could make all the difference.
Zen said:
Small favor to ask: Check/compare your modem firmware and carrier profiles version. Sometimes different devices like to ‘hang’ on different bands, which could make all the difference.
Aren’t those version numbers exclusive to each iPhone model?
Zen said: @Hale
Yeah, you’re right about the modem version. The carrier profile should be the same, though.
Gotcha. For the carrier profile, it’s the same on both phones.
It’s weird. I worked in Germany and Poland last winter with my iPhone 15 Pro, and it was solid on Deutsche Telekom. I roamed into Poland using the German carrier and had really fast speeds. I don’t think it’s related to your backup. I feel like the devices are ‘hanging’ on different bands. I’d put both in service mode and see which band each prefers. Your iPhone 15’s antenna is slightly different as well.