Mainly:KERNEL VERSION: Fremantle - 2.6; Leste - mainline, currently 5.x SUPPORTED DEVICES: Fremantle - N900 only; Leste - any device with mainline kernel support FOSS STATUS: Fremantle - some components closed; Leste - fully FOSS PROJECT STATUS: Fremantle - dead/frozen; Leste - WIP and should be supported into the future since it's fully FOSS HARDWARE SUPPORT: Fremantle - complete support for N900 hardware; Leste - WIP since some components, esp. 3D accel are still being worked on kernel-side And many more