Amazon sells the Alexa Show 5/7/10 devices.
The device SDK for those is free to use… Alexa Smart Screen SDK
However, Amazon has embedded a browser in their Alexa Show devices. Browsers are heavy weight and require many MB of RAM to run. So all of the Amazon Alexa Show devices have at least 1GB memory in them and quad core CPUs.
There is no requirement that a browser be used, Amazon has just done that for simplicity. You can use any GUI you want if you implement a ‘view host’ for the SDK to use. “Consumers of the APL Core Library can create their own APL view host in order to create Alexa experiences with visual renderings on their device or platform in the programming language of their choice.”
So the idea would be to implement the Alexa ‘view host’ as part of LVGL. Then I suspect anyone using that code would sign up for commercial support. If you get lucky Amazon might even use it.
AFAIK no one has implemented a ‘view host’ yet. Everyone is using an embedded browser and the associated hardware. Another plus – Amazon will actively promote you as a consultant to their OEMs who need this type of code.
Another possibility, companies like NXP have dedicated Amazon development systems. This is their voice only offering. https://www.nxp.com/design/designs/nxp-edgeready-mcu-based-solution-for-alexa-voice-service:MCU-VOICE-CONTROL-AVS
NXP does not offer an equivalent dev board with a screen. Likely because they don’t have a ‘view host’ implementation.