No personal data is collected, they aggregate data: "We do not track, collect nor store any personal data or personally identifiable information. We will do the opposite, since we will store devices IDs (or account IDs) which we can derive profile (Picture, bio) and IP addresses from. We do track individual people.
No tracking across devices "There is no way to know whether the same person visits a site from more than one device". We will track people across devices
All data is isolated to a single day. "All the data is isolated to a single day only. There is no way to know whether the same person comes back to a site on another day". We will specifically track that to measure retention.
They don't generate any persisted identifiers as they don't use cookies. But we will use cookies 2.0 if we store metrics information in the database. Even if we don't we recognize sessions from past days