Gravity Master GR-B100 / G-Shock Connected In-Depth Review

The Casio G-Shock Gravity Master model GR-B100 was first released in 2018. I'm aware of five variations of this watch, all using module 5536. The model featured in this video is the GR-B100-1A3, with a black and green color scheme and positive LCD display. The other versions all have reverse LCD (or negative LCD) displays. They are the GR-B100-1A2 (black and blue), the GR-B100-1A4 (copper, black and orange) the GR-B100GB-1A (black and gold) and the limited edition GR-B100WLP-7A (with a black, white and brown combination).

These watches all use Bluetooth to connect to Android or iOS devices which run the G-Shock Connected app. The app will set the watch to the correct time using an Internet-based time service from Casio. These watches do not have Casio's "Multiband 6" capability to set themselves to the correct time from long-range transmitters, but with regular connections to the G-Shock Connected app they will maintain correct time anyway. Without the app they will still run as standard quartz watches and remain accurate to within 15 seconds per month.

This model of the Gravity Master has Casio's "Tough Solar" power source, meaning the face of the watch has a built-in solar cell to charge the internal battery (or capacitor) and maintain the charge with regular exposure to everyday lighting conditions. It is also water resistant to 20 bars (or 200 meters). It has 5 alarms (with custom scheduling available), a stopwatch, countdown timer and a "World Time" second time zone display. The app allows the user to set almost all the functions that can also be set using combinations of buttons on the watch. The app also allows the user to save time and location "flight log points" which can be displayed on maps in the app and even exported to be used with other mapping software.

It's a powerful watch, loaded with features. At the time of this video's release the average price of these watches online is about $200 each (sometimes a little higher and sometimes a little lower than that).

And (spoiler alert) the watch I held up at the very end of this video is a GW9400 Rangeman.