To put it directly:
Devices like the Unihertz Titan, Titan Pocket, and Titan Slim are direct spiritual successors to BlackBerry. They run Android natively, feature physical QWERTY keyboards, and possess active developer communities building custom ROMs. Blackberry Passport Lineage Os
He executed the command. fastboot flash boot lineage.img . To put it directly: Devices like the Unihertz