Quick overview about the changes, more details found on Github (post link).

• Reduced memory footprint in flash memory: the analog watch face draws the background at runtime instead of using a pre-defined background picture and we moved the font for the navigation app to the external memory.
• Improved raise-to-wake algorithm and new lower-to-sleep functionality
• New weather service and new setting to select °C/°F
• The build system now allows to easily select which user applications and watch faces are built into the firmware
• Replace the node.js tool that convert the images (lv_img_conv) by a custom re-implementation in Python
• InfiniLink, the iOS companion app has a new maintainer! I will probably wait with the update for a week or two, as 1.13 came riddled with bugs.

Edit: Ah, have to wait for the new Gadgetbridge update anyways.

Unfortunately there is a bug with v0.77.0 of Gadgetbridge on Android 14, that means that it can't update InfiniTime. We have submitted a fix, which will be available in the next release of Gadgetbridge. In the meantime, you can use another device to do the upgrade or use a nightly build of GadgetBridge (it's recommended to use the no pebble flavour, as that can be installed alongside your existing GadgetBridge app).