I'd echo what Michael said, but add that we've laid out a very detailed vision of how NRV tokens will circulate within our economy, as well as how we will use reputation and moderation to foster quality content. Even though Sphere has a beta version in the app store, there is no detail about how the rewards work or how users will get their money (and based on what criteria).

Another key difference is that Sphere appears to be pure blockchain (i.e., everything is on the blockchain), whereas we are prioritizing user experience and using blockchain for transactions, but off-chain for content (for now).

It's a bit strange that Sphere's team bios have no links or information, other than a name and title. I'm sure that could be an oversight, but still weird.