INTRODUCTION
Smartphones have become an essential part of modern life, serving as communication hubs, productivity tools, entertainment centers, and even portable cameras capable of capturing professional-looking photos and videos. Over the years, manufacturers have continuously pushed the boundaries with faster processors, brighter displays, advanced camera systems, larger batteries, and next-generation connectivity, making today's smartphones more capable than ever before. While conventional smartphones focus primarily on sleek designs and premium aesthetics, a different category has emerged to meet the needs of users who work or spend time in demanding environments. Rugged smartphones are specifically designed to withstand drops, dust, water exposure, extreme temperatures, and the daily abuse that would quickly damage a typical handset. These devices are particularly popular among outdoor enthusiasts, construction workers, field technicians, travelers, and anyone who values durability and reliability above all else. Enter the FOSSiBOT F115 Ultra 5G, a rugged smartphone that combines the toughness expected from this category with modern smartphone features and 5G connectivity.
FOSSiBOT (Shenzhen Qichang Intelligent Technology Co., Ltd.) created by an innovative team of engineers. FOSSiBOT focus on research and development of portable, efficient, green, clean, natural environmental protection and sustainable renewable energy. In Autumn of 2022, we released our first flagship model F2400, using the latest dual inverter technology, fashionable appearance design, the improvement of the function details, meet the demand of all of your portable solar power.
The F115 Ultra is one of FOSSiBOT's most ambitious rugged smartphones, combining extreme durability with a feature set rarely seen in the mobile space. Powered by the MediaTek Dimensity 7100 5G 6nm octacore chipset, the device pairs 12GB of RAM, expandable up to 32GB through virtual memory, with 256GB of internal storage for demanding applications and multitasking workloads. A large 6.78-inch FHD+ (1080x2460p, 396PPI, 530cd/m2 brightness) display with a 120Hz refresh rate provides a smooth viewing experience, while the enormous 20000mAh battery is designed to keep the phone running for days between charges. The standout attractions are without doubt the integrated thermal imaging camera, transforming the F115 Ultra from a rugged smartphone into a practical diagnostic tool for both professionals and outdoor enthusiasts (enables users to visualize heat signatures, making it useful for equipment inspections, outdoor exploration, fault detection, search-and-rescue scenarios, and numerous professional field applications) and the 64MP ultra-long-range night vision camera (OmniVision OV64B40) capable of seeing up to 50 meters in darkness. Of course, the F115 Ultra is also equipped with a 50MP main camera (SONY IMX766) and a 32MP front-facing (SONY IMX616 - selfie) camera for regular recording. Further enhancing its utility is an integrated 1200-meter 8MP laser rangefinder camera (SK Hynix HI847) for precise distance measurements. Running Android 16 and protected by IP68, IP69K, and MIL-STD-810H certifications, the FOSSiBOT F115 Ultra is designed to serve as far more than a conventional smartphone, positioning itself as a multi-purpose outdoor and professional tool built for demanding environments.
SPECIFICATIONS AND FEATURES
PACKAGING AND CONTENTS
FOSSiBOT uses an orange box to ship the F115 Ultra the front of which just has their logo.
The product specifications, company details and the Serial Number and barcode are all printed on stickers located at the rear.
Packing is very good with the entire bundle being enveloped in a formed piece of soft foam.
Along with the F115 Ultra inside the box you'll also find a hand strap with two screws and a small screwdriver, USB-C charging cable, wall charger (region specific), SIM card pin and the user manual.
THE F115 ULTRA
From the factory FOSSiBOT has a sticker on the 6.78" screen that points to the main product features.
Above you can see how the Xiaomi 15T compares to the F115 Ultra in terms of size.
It may not be as rare as it once was but having such a large screen on your smartphone (and a Corning Gorilla glass one at that) is always a good thing in my book.
As you can all tell the screen comes with a protective film from the factory.
On the right side of the F115 Ultra we find one of the hand strap mounts, volume up/down buttons and the power on/screen on/off and Gemini launch button (also acts as fingerprint sensor).
You can position the hand strap either at the top or bottom of the F115 Ultra so there's another mount on the opposite end.
On the other side we also find two hand strap mounts (top/bottom), microSD/SIM card slot, customizable red button and a dedicated microphone mute button.
At the front of the F115 Ultra we find the 1200-meter 8MP laser rangefinder laser and camera.
On the opposite end we find the USB-C charging/data port (protected by a rubber cover) and a lanyard area.
Turning the F115 Ultra over we see that most of the rear is textured while at the top FOSSiBOT has placed the IR light (purple) which is surrounded by the 50MP main camera (top left), thermal camera (bottom left), flash (top right) and the IR camera (bottom right).
OS
As with most Android 15/16 based smartphones the layout is identical (the Thermal tools icon of course stands out).
Same goes for the drop-down menu (although it does have some extra icons by default).
Again, the F115 Ultra just like with the F116 Pro is not bloatware.
The menus again are almost identical to those of most current Android smartphones.
Once again even though the Duraspeed feature cam be very useful I do recommend turning off if you need on-time alerts from applications like Viber or Teams.
Of course you can also check the model hardware specifications and certifications.
CAMERAS
Quality of both the full resolution (50MP - top) and regular (bottom) modes is very good, during the day.
For night shots since the F115 Ultra has an IR camera the end result is what you'd expect really.
The thermal imaging app is not something we see a lot with smartphones and yes, for me it's what makes the F115 Ultra really special.
Resolution is also good, certainly not the best for a thermal camera but good.
The app has several measurements and parameters who can choose/adjust.
There are also 16 different thermal palettes you can choose from.
The rangefinder camera may not be as interesting as the thermal camera but it may actually be as useful for certain users.
TESTING METHODOLOGY
Since some of you requested more benchmarks, I have decided to use the following apps to review the performance of smartphones, GeekBench 6, GeekBench AI, 3D Mark, GFXBench, Passmark and AI Benchmark. All tests will be repeated a total of 6 times and the average numbers will be then recorded in the charts. Unfortunately, due to certain brand policies it seems that some of these benchmarks can't be run on every smartphone out there so whenever that's the case those results will obviously not be included in the review.
For all of you wondering just how smartphones do regarding mobile data (4G/5G and above) I will be using the SpeedTest app from the same location (roof) and with the same SIM card (Vodafone) for all models. This may not be an 100% accurate test (many variables), but it should be a good indicator of mobile data performance.
Finally, since some of you requested it, I’ll be using an 65W fast charger with the smartphones I test to see just how fast they can go to 80% and 100% (could use an even higher wattage charger but for most people 65W is the way to go).
TEST RESULTS – GEEKBENCH 6 / GEEKBENCH AI / PASSMARK / AI BENCHMARK
TEST RESULTS – 3D MARK / SPEEDTEST / BATTERY
CONCLUSION
As a complete package, the FOSSiBOT F115 Ultra successfully delivers on its promise of being far more than just another rugged smartphone. Yes, it may not be the fastest model out there but it should be more than plenty for most usages. Its standout strengths are unquestionably its exceptional durability, integrated thermal imaging camera, long-range night vision system, and practical measurement tools, including the 1200-meter laser rangefinder, which transform the device into a genuine field companion rather than a simple communication device. Battery life is equally impressive since during my very long testing period, the massive 20000mAh battery regularly delivered up to eight days of use between charges, thus eliminating the range anxiety associated with most modern smartphones. The large 6.78-inch 120Hz display further enhances the experience, providing ample screen real estate for navigation, measurements, media consumption, and thermal imaging analysis. The compromises are largely predictable and stem from the same features that make the device unique. With dimensions of approximately 185.5x87.4x30.4mm and a weight approaching 700g, the F115 Ultra is undeniably large, thick, and heavy compared to conventional smartphones, making one-handed operation and pocketability challenging. However, for users seeking a rugged smartphone capable of thermal inspections, night vision imaging, distance measurement, and multi-day battery life, these trade-offs are likely to be acceptable. Ultimately, the FOSSiBOT F115 Ultra occupies a niche of its own, offering a combination of features rarely found in a single device and establishing itself as one of the most capable utility-focused rugged smartphones currently available.
With a current retail price set at USD599.99 inside the USA (Amazon.com) and for around 590Euros inside the EU the F115 Ultra 5G Rugged Smartphone by FOSSiBOT is priced well for what it offers. Again, this is a smartphone aimed towards outdoor enthusiasts, construction workers, field technicians, travelers and professionals in general who can make use of its features so users looking for a gaming model should obviously look elsewhere. Overall however I've been extremely satisfied with the all-around performance of the F115 Ultra by FOSSiBOT so the Golden Award is in order.
PROS
- Very Good Build Quality (Rugged)
- Mediatek Dimensity 7100 (Overall Performance)
- 6.78” 120Hz Screen
- IP68, IP69K, and MIL‑STD‑810H Certified
- 12GB RAM (Expandable To 32GB Virtual)
- 256GB Storage
- 32MP Front / 50MP Primary Rear Camera
- 64MP Long Range IR Camera
- Thermal Imaging Camera
- 1200 Meter Rangefinder Laser With 8MP Camera
- 20000mAh Battery
- Available OS Features
CONS
- Price (For Some)
- Size & Weight
