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1Clear out junk files and repair common Windows errors2Scan for outdated or missing drivers - takes under a minute3Repair Windows errors before they cause bigger problemsThe Casio G-SHOCK MUDMAN GDG-B100 pairs a memory-in-pixel (MIP) LCD and red LED backlight with Bluetooth phone alerts and training functions. It adds connected features to a rugged digital watch, rather than turning it into a full smartwatch. Casio describes the display as readable in bright outdoor conditions, but that is a manufacturer claim, not an independent comparison.
What the GDG-B100 adds
Casio lists three versions: GDG-B100-1, GDG-B100-1A3 and GDG-B100-1A5. The model’s main changes in emphasis are its MIP display, Bluetooth-connected functions and training data. “Biggest digital upgrade yet” is a useful headline framing, but Casio’s specifications do not establish a feature-by-feature history proving it is literally the largest upgrade in the MUDMAN line.
![Casio GW-9500-1JF [G-Shock Master of G Series MUDMAN Triple Sensor Model] Watch Japan Import July 2023 Model](https://m.media-amazon.com/images/I/41bbHfxiCdL._SL160_.jpg)
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MIP screen and red backlight
MIP means memory-in-pixel: the display technology presents the time and measurement information on the LCD. Casio says it provides high-definition display and readability in bright outdoor spaces and direct sunlight. That is Casio’s claim; no independent legibility test or comparison with another watch is available here. An automatic red LED backlight is specified for low-light viewing. Casio’s GDG-B100 product page describes both features.
Phone alerts, not message replies
Bluetooth links the watch to the CASIO WATCHES app. Supported phone alert categories include incoming calls, emails, social posts, calendar notifications and reminders. The official feature description covers receiving alerts; it does not specify replying to messages from the watch. Vibration alerts also cover selected training targets.
#1 Best Overall
- Case size (L× W× H): 52 × 46.3 × 16.3 mm
- Shock Resistant, Mud Resistant, 200 meter water resistant, Auto Dual EL Backlights with Afterglow, Low Temperature Resistant, World Time - 29 time zones (48 cities), city code display, daylight saving on/off, 1/100 second stopwatch, Measuring modes: Elapsed time, split time, 1st-2nd place times, 1/100 second stopwatch
- Countdown timer -start time setting range: 1 minute to 24 hours (1-minute increments and 1-hour increments), Auto-repeat, progress beeper, Four Multi-function alarms & 1 snooze alarm, Hourly time signal, Full auto-calendar ,12/24 hour formats, Button operation tone on/off , Flash alert
Other app-linked functions include automatic time adjustment, settings, world time, activity history, life-log information, distance correction using smartphone GPS and a phone finder. These are useful connected-watch functions, but the GDG-B100 is not described as offering a full smartwatch interface.
Training functions and the GPS distinction
The watch uses an accelerometer for step counting and calculates distance, speed, pace and calories. Casio also lists stopwatch timing, lap-time storage and an interval timer with up to five time settings. Training data can cover up to 100 runs.
Rank #2
The GPS detail matters: Casio says the distance can be corrected using GPS from a paired smartphone. The listed feature is phone-based distance correction, not a built-in GPS receiver in the watch. Calculated workout measures should not be confused with independently verified accuracy.
The Tool Desk
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Casio describes the GDG-B100 as shock-, dust- and mud-resistant, with a carbon-fiber-reinforced resin case structure. For the GDG-B100-1A5, Casio UK lists these specifications:
Rank #3
- Triple Sensor (compass, altimeter/barometer, and thermometer)
- Solar Powered
- Radio- Controlled
- Bluetooth Mobile Link
- Double LED
| Specification | Casio UK listing |
|---|---|
| Water resistance | 200 metres (20 bar) |
| Case dimensions | 63.6 × 49.6 × 16.2 mm |
| Weight | 66 g |
| Battery | CR2032; approximately two years |
These are manufacturer specifications and estimates, not independently measured results. The cited UK listing specifies a replaceable CR2032 battery and an approximate two-year life; it does not describe the watch as solar-powered or rechargeable. Dimensions, weight and battery details are on Casio UK’s GDG-B100-1A5 page.
GDG-B100 or GW-9500?
The GW-9500 is another MUDMAN, but it is not a like-for-like test against the GDG-B100. Casio’s product descriptions emphasize different capabilities, so the practical choice depends on whether connected training or sensor-based outdoor tools matter more.
Rank #4
- ●Sunrise and sunset time display
| Consideration | GDG-B100 | GW-9500 |
|---|---|---|
| Display | MIP LCD with automatic red LED backlight | Duplex (dual-layer) LCD |
| Outdoor tools highlighted | Step tracking, training calculations and smartphone-linked distance correction | Digital compass and barometer/altimeter functions |
| Connectivity emphasis | Bluetooth, CASIO WATCHES app and phone notifications | Compass and sensor capabilities are highlighted in Casio’s announcement; equivalent notification features are not established by that source |
Casio details the GDG-B100 on its product page and described the GW-9500’s dual-layer LCD and sensors in its 2023 GW-9500 announcement. Choose based on the functions you need; these descriptions do not establish that one model is more accurate or universally better.
UK launch price and availability
T3 reported on October 1, 2026 that the GDG-B100 would cost £200 in the UK and be available from October, in black, dark green with orange accents, and a sand-colored strap with black bezel. That is launch reporting for the UK, not confirmation of current stock or pricing in other regions. The UK-listed variant GDG-B100-1A5 is identified by Casio as a new October 2026 product. Check a current regional listing for availability and price before buying. T3’s launch report provides the reported price and color descriptions.
Quick Recap
Best Value
- For the fearless adventurer and nature lover, a robust and tireless Master of G MUDMASTER with case and bezel made of durable carbon and environmentally friendly materials.
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
