What is a Dual Sim Smartphone?

A Dual Sim Smartphone is basically a cellphone with 2 slots for Sim Cards.
the very first Dual Sim Smartphones came from China around 2005 and had a simple switch function to select a sim card.

In 2006, Coolpad, a Chinese manufacturer, brought the first Dual Sim Smartphone to the market with 2 sim cards being permanently active at the same time.
With this Dual Sim Smartphone, it was for the first time possible to be talking on one line, then putting this call on hold while taking a call on the second sim card and juggle the lines around.

More and more manufacturers started to develop Dual Sim Smart Phones, but the major cellphone brands were still reluctant to offer these cellphones globallly.

Especially in Europe providers were not happy about the idea of Dual Sim Smartphones as their sales models were based on selling a cheap cellphone (sometimes for 1 Euro) with an expensive provider contract and expensive calling rates. On top of that the cellphone comes with a provider lock so it is impossible to use the phone with a different sim card. A model that is still very wide-spread in Europe and North America.

Gradually the big manufacturers like Samsung started to offer more and more cellphones in a Dual Sim Smartphone version.
However, very often these cellphones would not be available in Europe or only available for the Asian markets.

With some Asian countries using different standards like CDMA ( Code Division Multiple Access) as opposed to the widely common GSM (Global System for Mobile) a consumer has to look closely at the Dual Sim Cellphone in order to find out whether it would actually work in his country or not.

In the development of the Dual Sim Cellphone another variation was introduced.
Unfortunately not all of today’s Dual Sim Smartphones have the same Dual Sim fonctionality:
3 Types of Dual Sim Cellphones can be found. Very often, the consumer has to look really closely in order to identify the Dual Sim functionality type used in a Smartphone.
Very often a missing Dual Sim element is disguised in a marketing bubble, which does not necessary make it easier for the consumer.

The 3 types of dual sim functionality found in today’s Dual Sim Smartphones are:

1.Dual Sim Full Active
2. Dual Sim Standby
3. Dual Sim Dual Standby

1.Dual Sim Full Active:
Only those Dual Sim Cellphones that are Dual Sim Full active do have 2 really independent lines . These phones have 2 GSM sending and receiving units. This means that both lines – both sim cards – are permanently available all of the time. So even if one sim card is in use, you can still receive calls from the other sim card.

2. Dual Sim Standby
This is the most common Dual Sim form found in today’s Dual Sim Smartphones. Cellphones with this dual sim feature can take phonically on each of the 2 lines (sim cards) However, if one sim card is in use, the other sim card is not available.
Very often, this important feature is not made clear in product descriptions for obvious reasons.

3. Dual Sim Dual StandbyThis is the worst of the 3 options as the dual sim function is made by a call divert.
Sometimes this feature is disguised as a „dual sim reachability“ feature.So you may as well use the cheaper option of a dual sim card.

Generally speaking, it is still very hard for the consumer to find out about the exact dual sim functionality of a Dual Sim Smartphone.

Without a doubt, a Dual Sim Full Active Smartphone is the most convenient form of a Dual Sim Phone.
Our advice for the consumer is to have a close look at the kind of dual sim function he really
requires. Many times the required function can be achieved with a dual sim card.

A dual sim adapter card is an even better option if you are an IOS user as there are no IOS-based Dual Sim Smartphones on the market yet, or, if the cellphone you are interested in does not come in a Dual Sim Full Active version.