In this community anything that isn’t open source is not going to be relevant to the majority. It sure does look like a competent product though but I question it as an alternative to Google since it’s going to be tough to survive when one is pre-installed and automatic without any user intervention on pretty much every android phone and the other I hadn’t even heard about until now and I’ve researched alternatives…

I think they’d be smart to make their free version open source to assuage the concerns about risking that the product dies and all tagging etc becoming useless / wasted effort. Even though I understand the reluctance because the primary motivators for going premium aren’t really open source compatible (pay for more devices etc.)