Samsung MultiStar update brings several improvements
New updates to Good Lock including new multistar app with more multitasking options : r/GalaxyNote9
Samsung MultiStar - Samsung Members
Samsung releases a new Good Lock Module, MultiStar. Can force any application to splitscreen and keep both windows active. (ie: netflix in splitscreen, or play 2 games at the same time). :
MultiStar - Samsung Members
Multistar update 3.0 - Samsung Members
Samsung MultiStar Update Brings Cover Widget to Galaxy Z Flip 5
How to use Samsung MultiStar to try real multitasking - Android Authority
Samsung Good Lock update brings enhanced Multi Window functionality - SamMobile
Samsung MultiStar for Android - Download the APK from Uptodown