A couple of reasons. One, they borrow money and pay employees with stock. Which does dilute the shares. But most startups have to get money from somewhere and none of those places are typically good. Borrowing money always cost you something. Two, it was trading at around $0.10 not too long ago. You have to assume some are cashing in on those gains and selling off to take some profits. That will naturally dip the stock some. And when you are a penny stock, a few cents in big percentage.
No big deal. My prediction is that with each step up 25-50%, there will be some pull back before the next step up.