When I was “removed” from my job back in May last year, I bought my new phone from a grey market supplier (also called a parallel importer in Turkey), which I neither support nor recommend, but did it for the sake of using my severance in a more proper way. The full model number is the SM-G9650 / DS dual-SIM card with 128 GB of storage space.
Of course, this new phone model supports VoLTE and VoWiFi technologies. Many of you would know, but let me summarize these two:
VoLTE (voice over LTE): Since the first versions of LTE did not support voice transmission and it still is a pure data packet system, when you get calls with an old phone and/or old infrastructure, your device automatically falls back to 3G technology to handle the voice transmission. VoLTE solves this as it sends voice not in a separate voice comm layer but makes it a QOS-wise well-treated data packet. For example, if your phone is used as a wireless access point, you will not experience interruptions when switching between 4th generation and 3rd generation networks. In rare cases where 4G / LTE access is available but 3G access is not available, calls are not interrupted or missed. Though I should confess that I haven’t ever been to a place where 4G network had better coverage and/or performance than 3G.
VoWiFi (voice over WiFi or WiFi calling): Where there is no cell network (basements, airplanes, even overseas if you do not want to pay excessive roaming fees!) but you have a terrestrial internet connection, this tech allows you to make calls as if you are calling from your normal cellular line. For example, even if you are in another country, even if your phone is in airplane mode and you are only connected to the Internet via WiFi (yeah, ethernet connection works as well in case you wonder), you can still make calls where they are treated as minutes on your tariff. It is like making calls via WhatsApp, but you can use the standard phone system without any software.
Features of the model I own
Samsung Galaxy S9 + – SM-G9650 / DS
Qualcomm Snapdragon 845
128GB storage + microSD slot
Dual SIM card support, 2nd SIM uses microSD slot
Android 9 (May 1, 2019)
One UI 1.0
Why couldn’t I use it?
When I bought the phone on May of 2018, it was working quite fast on LTE network (in Vodafone Turkey standards, I should add), but during the calls VoLTE would not kick in, while the VoWiFi was completely missing in the menu. This is usual! I thought it was normal because the bands and standards of LTE services around the world varied “wildly” and they changed from country to country, even from operator to operator. After a few days of internet searches, I gave up the idea of tampering with the software.
After the May 28 update
Although not as fast as Sony Mobile Turkey, the pace Samsung provides security updates pleases me. Especially considering the geographical and hardware differences in the products (consider Exynos and Snapdragon platforms). After a slightly delayed update last day, I noticed that both features were working on the phone. I tried them, working perfectly! No problem. How could that be?
Frankly, I was writing this article just to say that after an update these features worked. I didn’t look at the possible root of this bliss until I started writing. Then I searched through the Baseband version and I guess I found the reason. If you look at the information at this address, the following update lines indicate that an experimental VoLTE support has been added for a Chinese operator.
This means that the service infrastructure used by China Unicom is somehow compatible with the infrastructure here (at least in Vodafone). Because it was already compatible with service from other Chinese operators as the phone was released.
This article is a loose translation from its Turkish version which can be found here.