Dual-SIM smartphones are very convenient for those who use two different operators (for example, one for the Internet, the other for calls) or those who use separate numbers for personal and business purposes.
When buying such a smartphone, you need to know some features that will greatly affect the quality of communication and its capabilities.
DSDS or DSDA - which one to choose?
Dual-SIM smartphones can support one of the DSDS or DSDA technologies.
DSDS (Dual SIM Dual Standby) - Both SIM cards work in this technology, but only one of them can be actively used. For example, when a call is received to the first SIM card, it cannot receive second calls. Other users who try to call the second SIM will receive a message that the subscriber is temporarily unavailable.
This problem is partially solved by the call forwarding function, ie calls received via SIM2 are forwarded to SIM1. Forward calls are evaluated by the operator as an outgoing call.
Also, on some smartphones, the first SIM card will work in 2G / 3G / 4G (https://t.me/gsmgurus_FAQ/421) modes (for internet + calls), the second only for 2G (calls) for) can work. The reason for such restrictions is that one radio module is installed for both SIM-cards.
Most smartphones sold in our country work on DSDS technology.
DSDA (Dual SIM Dual Active) - This technology has no restrictions on the performance of SIM-cards due to the additional radio module. The subscriber can receive calls from both SIM-cards at the same time and the overall communication quality is also better. However, smartphones with DSDA technology consume more battery and the cost of such devices is higher.
Smartphones running DSDA technology are declining year by year and can be found mainly in devices made for China. As far as I know, HTC, LG, Asus, Huawei and Honor brands have produced DSDA smartphones.
What is the difference between single or hybrid SIM card slots?
There are two types of slots: separate SIM cards (for two SIM cards + memory card) and hybrid (for two SIM cards or SIM and memory card).
The second option is more common on most smartphones. If you plan to use two SIM cards and a memory card (microSD) at the same time, you will need to choose a smartphone with separate SIM cards and a memory card slot.
In the near future, all smartphones can be produced with a single SIM card and eSIM (what is an eSIM-card? (Https://t.me/gsmgurus_FAQ/825)) module. Currently, most flagship smartphones can use an additional SIM-card using eSIM technology.
Q: Do you know which smartphones with two SIM cards working at the same time (DSDA)?
