New figures from analysts M: Metrics show that EA Mobile's market share has decreased by more than five per cent this year.
During the three months ending October 2006, EA's share of new paid downloads stood at 26.5 per cent - down from 32.2 per cent in the previous period.
The M: Metrics report also shows that Glu Mobile has now secured the second biggest share of the market, pushing rival Gameloft into third place. Namco is at No. 4, followed by Hands-On Mobile, and the Walt Disney Internet Group has made an appearance in the top ten for the first time.
Just four out of the top ten publishers reported growth during the period - including independent company Gosub 60, which was up from No. 9 to No. 8 thanks to the success of titles such as Sudoku Deluxe and Blackjack Cheater.
"It's a very fluid space with a lot of close competition, so these rankings are constantly in flux. But directionally, it's certainly very encouraging," observed Gosub 60 CEO and co-founder Josh Hartwell.
"The business is on a solid growth path and satisfying our aggressive forecasts. At the end of the day though, we still consider ourselves a boutique publisher. It's not our goal to stuff the shelves, but rather to deliver the highest sku efficiency possible.
"We don't go to the carriers with a massive slate of titles; instead, we offer five or six carefully chosen, high-quality games each year. Right now, we've got seven active titles on the decks, whereas the other Top 10 publishers have anywhere from 22 to 93."