Another round of startup layoffs:

News broke yesterday that Pebble, the seven-year-old smartwatch pioneer based in Palo Alto, is laying off 25 percent of its staff – or 40 of 120 employees – amid increased financial concerns. CEO Eric Migicovsky told TechCrunch that he blamed a more cautious outlook from tech-focused VCs as the primary reason for the layoffs. Pebble has raised $28M in debt and venture financing over the past eight months, in addition to a second wildly successful $20M Kickstarter campaign.

What’s the hierarchy of engagement?

Sarah Tavel of Greylock Partners speaks to the importance of understanding how a product is built to maximize and leverage user engagement. The hierarchy of engagement, as Tavel lays out, has three levels: 1) Growing engaged users, 2) Retaining users, and 3) Self-perpetuating.

YC Demo Day, round two:

Y Combinator kicked off Demo Day 2 for its Winter 2016 batch in Mountain View yesterday, where its second batch of 59 startups pitched to a full house of investors and press. Among yesterday’s presenters are OpenTrons, a robot for automating the web lab to accelerate life science research, and SHRI, a solution for converting human waste into drinking water. TechCrunch has the full recap on Day 2 and the favorites from Day 1 here.

Interactive data visualizations on the Unicorn Leaderboard

This quarter has already seen 8 new unicorn companies. In 2015, CrunchBase recorded 77 new unicorns, an average of 19 per quarter. Check out the latest investors and companies on our interactive timeline visualization.