### Cardputer:
- Fix keyboard issue with up/down button conflict when selecting switch
- Fix backlight flickering
### UI improvements
- Removed a 3 pixel border that went around the entire desktop environment
- Improved system layout (GuiService)
- Statusbar: improved layout (mainly margin/padding)
- Toolbar: fixed margin/padding of all buttons, fixed alignment of all content
- Improved layout/UI of many apps
### Other
- Update LVGL to 9.3.0 official release (was dev version)
## New features
- Implemented support for app packaging in firmware and `tactility.py`: load `.app` files instead of `.elf` files. Install apps remotely or via `FileBrowser`.
- Ensure headless mode works: all services that require LVGL can deal with the absence of a display
- Service `onStart()` is now allowed to fail (return `bool` result)
- Added and improved various file-related helper functions
## Improvements
- Completely revamped the SystemInfo app UI
- Improved Calculator UI of internal and external variant
- Fix Chat UI and removed the emoji buttons for now
- Fix for toolbar bottom padding issue in all apps
## Fixes
- Fix for allowing recursive locking for certain SPI SD cards
& more
- Fix bug in Development app: when launching/stopping external app due to LVGL being stopped and a timer still being active (sometimes, as it's a race condition)
- Added TODO to fix the same bug in other apps
- Update external app SDKs to `0.5.0-SNAPSHOT`
- Add app path get() functions to `TactilityC`
- Improved `Dispatcher` and `DispatcherThread`
- Improved `PubSub` (type safety)
- Created test for `DispatcherThread` and `PubSub`
- Save properties files on app exit (various apps) by posting it to the main dispatcher (fixes UI hanging briefly on app exit)
- Fixed bug with `SystemSettings` being read from the wrong file path.
- `loadPropertiesFile()` now uses `file::readLines()` instead of doing that manually
- Increased timer task stack size (required due to issues when reading a properties file for the very first time)
- General cleanup
- Created `EstimatedPower` driver that uses an ADC pin to measure voltage and estimate the battery charge that is left.
- Cleanup of T-Deck board (updated to new style)
- Move various settings to `/data/settings` and `/sdcard/settings`
- Fix for `Gui` and `Statusbar` errors on startup (LVGL start)
- Implement Development service settings as properties file
- Rename `service::findManifestId()` to `service::findManifestById()`
- Renamed various classes like `BootProperties` to `BootSettings`
- Renamed `settings.properties` to `system.properties`. Code was moved to `settings` namespace/folder
- `DevelopmentSettings` is now in `settings` namespace/folder (moved from service)
- Made an external app from internal Calculator app
- Update tactility.py to v1.2.0 (fix bug with selfupdate)
- Added warning to Development service UI
- Add context to `SECURITY.md`
- Split `ObjectFileReader` and `ObjectFileWriter` into separate cpp files
- Fix related to GPS config read errors
Various improvements and new internal APIs including a new Development service+app which allows `tactility.py` to upload and run applications remotely.