Ann: ICI's New Game Claw Stars Early Trial Results, page-12

There's no way of knowing exactly, though you could estimate the installs would be around 12,000 - 14,000, as Google Play is currently showing 10,000+ for around a week now (as @ASA12627 said). This estimate is based off how fast it has moved up recently.

What's good to know is that Claw Stars only has to get slightly higher in Australia, US, Canada and Japan's Arcade Revenue rankings to make it into the Top Revenue Games and Apps rankings for those countries.

All of this is especially awesome considering Claw Stars appears to have very minimal marketing outside of being advertised within other iCandy games