Two years after the introduction of the first G-Shock models that had the ability to communicate with a smartphone via Bluetooth connection, Casio is introducing the second generation of these watches with new additional functions. Supplied with Generation 2 Engine, as well as with the previously used Bluetooth v4.0 technology which allows small energy consumption, these new G-Shock timekeepers now allow two-way connection. In other words, the new watch can control some of the phone functions and vice versa. It is very commendable that these G-Shocks are compatible with both iPhone and Android operating systems. They are quite affordable with the price of $180 or $200 (depending on the size) and they include the characteristic resilience and multitude of functions that are usual for the timekeepers from the Casio G-Shock series. The digital newcomers are available in two case sizes which are both quite substantial, as well as in several different colors.
Two-Way Connection: Use your Watch to Play the Music on the Phone, or Adjust the Timekeeper’s Alarm with the Phone
The second generation of Casio watches is compatible to iPhone 5, iPhone 4S and Samsung Galaxy S4. However, there are some differences regarding which smartphone you are using in regard to the supported functions. The main shared trait is ability to use your watch to control the music on the phone. More accurately, the watch can play, pause, move to the next song and adjust the volume of the phone’s own music player. When it comes to the other direction of communication, the phone can be utilized to activate world time, alarm, countdown timer and some other functions. Some of other features that are able on both types of devices are time correction via the phone, incoming call, e-mails, SMS and social network message alerts, the use of the watch to silence the incoming call with a simple tap. Moreover, there are very useful features that can notify the wearer that the connection between two devices is lost and our favorite which helps you find the phone. It is likewise very important to say that the range of communication between the phone and the watch is about 2 meters.

Casio G-Shock Bluetooth Watch
The G-Shock’s Standard List of Features
Apart from including ability to interact with a smartphone, new Casio products also come with the packed list of features that are common for G-Shock timekeepers. While Bluetooth indications sit in two separate windows at the top of the dial (one of them is showing whether the connection is active, while the other, a slightly larger one, is reserved for phone alerts), the actual watch displays still occupy the biggest portion of the dial. Among the host of supported functions which the newcomers from G-Shock series support, there are: world time with 100 cities and 35 time zones; 1/100 punctual stopwatch that can measure intervals to just under 1000 hours and includes elapsed, split, 1st and 2nd time features, five independent daily alarms, countdown alarm, LED backlight with adjustable illumination duration; full auto calendar; power saving; the choice between 12/24 hour formats; low battery warning; as well as automatic termination of the Bluetooth link after the fixed period. It is all provided with a Japanese quartz module which is fitted into a case designed in accordance with the G-Shock extreme toughness standards and with waterproofness to 200 meters. The movement has common accuracy for a quartz caliber which is within 15 seconds per month. As Casio says, these watches include a battery that enables them to function for as much as two years. This impressive longevity is however achieved only if the wearer of the watch does not utilize the connection between it and the phone for more than 12 hours per day.
Large or Larger
As it has already been mentioned, there are two available sizes which are both made in several different color schemes. The smaller (yet still quite chunky) version GB-6900B is with the case diameter of 53.2 mm, the thickness of 18.7 mm and the weight of 65 grams. It costs $180 and is available in two black versions: the most classical looking black variation has the green display (the GB-6900B-1), while the other one comes with blue accents on the dial and negative display (the GB-6900B-1B). There are also two more models with negative displays: a gray version with gold accents (GB-6900B-3) and a white one with gray details on the face (GB-6900B-7).

Casio G-Shock Bluetooth GB-X96900B-2 Watch
The bigger sized G-Shock from the second generation of watches with Bluetooth connectability is with the massive width of 57.5 mm, the height of 20.4 mm and the weight of 82 grams. This timepiece with the starting reference number GB-X6900B is made in the same basic black version with a green digital display (the GB-X6900B-1), but also in more colorful versions. The first one is with light blue and black negative display with blue indications (the GB-X6900B-2), whereas the second variation includes red case and strap and a gold-colored dial (GB-X6900B-4). The bigger-sized version of the newcomer is only slightly more valuable with the price of $200. Regardless of the specific mode, these watches come with cases made from resin and bands from the same material and the color that matches the cases.
If you are interested in more watches with the ability to connect with a smartphone, read our review of Citizen Proximity model which is, unlike the Casio’s newcomer, only compatible with an iPhone.