Really... Is it that hard to open the history button on the webpage where you download the FW?
https://www.yitechnology.com/yi-4k-action-camera-firmware
OK - so let me copy/paste it here for you
v1.7.8
Added Slow Motion resolution choice, supports 1920x1080 and 1280x720
Added new frame rates for certain resolutions, supports 4K/24FPS, 2.7K/24FPS, 2.7K/48FPS, 1920x1440/24FPS, 1920x1440/48FPS, 1920x1080/24FPS, 1920x1080/48FPS
Added DNG for Time Lapse Photo Mode when it is set to Continuous
Added Mode Switch, Normal Mode, Current Mode for Bluetooth Controller
Added shutter speed choice for Photo, Timer and Time Lapse Photo Mode, supports 1/500s, 1/125s, 1/30s, 1/8s, 1/2s and 1s
Added the battery percentage display
Optimized the album user experience
Optimized SD card compatibility
Optimized image effect, improved high contrast
Optimized Live Streaming feature and removed watermark
Fixed EXIF time stamp bug
Fixed the “Bluetooth pairing failure” issue
v1.6.10
Added Time-lapse video definition choices, supports 1080P and 960P
Added Russian, Spanish and Japanese language
Added Time-lapse photo DNG feature
Fixed time issue when video recording in large files
Fixed the system lag issue after viewing the album
Optimized SD card compatibility
Optimized Native effect when manually adjusting White Balance
Optimized system stability
v1.6.1
Added manual metering and exposure lock
Added DNG image format
Added Chinese language
Adjusted some of the resolutions bitrate
Adjusted "Video+photo" mode. Removed "Picture capture successful" prompt
Optimized stability of album
Optimized UI
Optimized image quality of the red tone
Optimized manual white balance image quality
Optimized Flatcolor Mode, unbound with Daylight configuration
v1.5.6
Fixed issue with ending time-lapse photo mode
Fixed issue of “In Processing” prompt when file deletion has failed
Fixed the crash issue when turning on AV-OUT and Quickview
Fixed firmware upgrade issues
Optimized UI
Optimized ability to turn off the camera when in Quickview
v1.5.1
Adds Chinese language choice
Adds SD Card Optimization
Optimizes USB LED function which syncs the battery lights indicator
Optimizes SD card compatibility
Fixes crash issue with firmware downgrade
v1.4.23
Added support for large files, and made adjustments to algorithms for SD Card.
Added Battery-Save mode option under timer mode.
Added support for USB-LED Indicator under Advanced Settings
Fixed a bug that caused issues with photo resolution in file manager
Fixed a bug with AV-Out
Improved the stability during updates
Improved algorithms for battery level indication
Improved audio output in file manager
Improved SD card compatibility
v1.4.14
Add multi-language (EU);
Add enlarge and drag photo function (Double click the photo when in no status info);
Add Quick View;
Add Audio Effect option;
Add Mic option;
Add Video/Photo [ISO Max], [ISO Min] option;
Change default format of 32GB SD card to exFAT;
Fix the file name start from 0 when shooting videos/pictures after formatting SD card;
Fix when shooting in 120FPS or 240FPS the possible freeze issue;
Fix the unresponsive issue when fast previewing pictures;
Optimize Bluetooth pairing, controlling;
Optimize time-lapse procedure;