Naninovel is currently in a final stage of open beta: all the core features are implemented and the engine is already being used in multiple commercial projects, but there is still a probability of breaking changes prior to stable release, which is scheduled for April 2020.
Minimum supported Unity version is 2019.3; this won't change throughout Naninovel v1.x releases. Support for new releases from TECH stream is added once they're out of beta.
It's recommended to stay on 2019 LTS stream (expected to release in spring 2020) to minimize production risks.
All the engine features are implemented using cross-platform APIs and are expected to be compatible with all the platforms Unity can target.
The following platforms were tested for compatibility:
"Medium" and "High" managed bytecode stripping profiles are not supported. Either disable the stripping or use the "Low" profile (set by default).