I picked up an F50 years ago but never got around to using it. Recently, since I've been out and about more often, I dug it out of storage and found it was still brand new! I went ahead and got a 5G data plan (the Little Whale Card), and the speed is really impressive. Of course, that's thanks to the nearby cell tower and the fact that it's not crowded with users, which is why I'm getting such great speeds.
While browsing online, I discovered this device can unlock some advanced features, such as viewing real-time device status, signal strength, data usage statistics, device temperature, and locking specific cell towers or frequency bands. These are essential functions for anyone using the F50 as their primary device.
So Achao compiled a step-by-step guide on how to downgrade F50 from B15 to B09 and enable the advanced backend. It's incredibly detailed! Below are screenshots after successful completion.
Partial Feature Preview
Overall, having access to the advanced backend unlocks more gameplay features and functionality, and even allows you to use the Cat Plugin—which is pretty cool!
Origin of the Issue
But when I first turned on the F50, it prompted me to update the firmware. Seeing there was a new version, I naturally clicked to upgrade to the latest B15 firmware—only to later discover B15 doesn't support advanced background features. Talk about regret! So I started scouring the web for solutions.After some effort, I found the installation package and firmware files. It took a while of tinkering to downgrade the F50 back to the B09 version.
Why choose the B09 edition?
Overall, the B09 firmware version is the most stable one available and also the most widely used version.
Thank you
Special thanks to kano for the firmware package and tools!
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The tool itself is harmless, purely designed to let tech-savvy enthusiasts explore more interesting features. Therefore, please refrain from using this tool for any illegal activities and comply with local laws and regulations! Do not break the law! If you disagree with this policy, please close this webpage!
Tutorial begins
First, prepare the following tools: (Download links are provided in the text)
- F50 Device (B15 Firmware)
- Laptop/Desktop Computer
- One data cable (user-supplied)
- Firmware package (as mentioned in the text)
- Screen Mirroring Tool
- UFI-Tools
Creating tutorials is no easy task—please appreciate the effort! Note: Fees are solely as appreciation for tutorial production! If you agree, please proceed.
Do not attempt to use other firmware versions; this is exclusively for the B15 version.
This is a photo tutorial with numerous images, so it may take some time to load. Please be patient.
Thanks for the awesome tutorial!! Followed it step by step and nailed it on the first try!! 💪💪💪