why the price is down now i was thinking that the new contract with eth is a good news and it well affect the price to go up
This is cryptocurrency, there's a large tendency to "sell the news".
Even now, everyone who is upset about the announcement of MobileGo has simply not read the whitepaper. If they had they would know that MobileGo takes away from none of GameCredits features. In fact, a successful MobileGo will just mean millions of dollars for marketing the GameCredits Store this spring.