Alpha 8

• Android release
• Improved Windows builds
• Favorites support
• Jump-to-letter support
• Custom filters support
• UI improvements
• French translation
• Frontend chooser tool
• Performance improvements

Alpha 7

• Stable metadata format
• No more dependency on ES2
• Updated documentation
• Config file converter tool
• Page up/down support
• Debian repo
• Spanish translation
• Lots of minor tweaks

Alpha 6

• Stable theme API
• Stable config file format
• Documentation, tutorials and guides
• 3D support in themes
• Improved static builds
• Raspbian Stretch support
• Huge amount of internal changes (for API stabilization)
• Bunch of optimizations and fixes

Alpha 5

• Steam support
• Improved ES2 compatibility
• New logo and loading screen
• Theming API
• Initial config file format
• Automatic testing
• Bunch of optimizations and fixes

Alpha 4

Main changes:

• added favorite support
• added searching and filtering support
• added support for calling scripts before launching a game and after returning from it
• video files no longer need the -video suffix
• added multiple gamepad support
• added gamepad analog navigation support
• translators no longer need to touch the source code to add new languages
• added confirmation dialog before shutdown and reboot
• added error messages when no games have been found and when the selected theme couldn't be loaded
• general ui improvements
• redesigned the settings menu
• added fullscreen support for desktop users
• added support for overriding the user's home directory
• general improvements, optimizations and bugfixes

alpha3

Changes:

• multilanguage support
• external script support
• file logging
• external theme support
• scrolling details text
• Qt 5.7 support
• less dependencies
• bugfixes and optimizations

alpha2

Release post and install guide: https://retropie.org.uk/forum/topic/9598/announcing-pegasus-frontend/164

Changes:

• main menu
• reboot/shutdown support
• mouse support
• gamepad config screen
• documentations and wiki
• improved gamepad support and config screen
• optimizations
• build infrastructure improvements
• update to Qt 5.9

alpha1

• basic project structure
• basic layout and initial theme
• basic ES2 XML compatibility
• portable asset finding
• multimedia (incl. video) support
• backend API structure
• screen resolution independent drawing
• basic gamepad navigation
• can launch games