Homer Simpson is not quite keeping up with the Kardashians.

Electronic Arts is watching as its biggest (but aging) mobile games are starting to wane in popularity. Publishers like Glu, King, and Blizzard, on the other hand, are all seeing their recent releases climb the mobile charts. This is an example of the difficult and competitive mobile-gaming landscape that can prove a challenge even for the biggest game makers. With an estimated $20 billion in consumer spending on smartphone and tablet apps on the line in 2014, few publishers are willing to sit it out.

The Simpsons: Tapped Out, which debuted February 2012, and The Sims Freeplay, which hit in December 2011, are two of EA’s biggest hits on smartphone, but each look like they are on their way out, according to Cowen & Company analyst Doug Creutz. The Simpsons dropped nine places to No. 19 on the iPhone’s top-grossing chart from June to July. The Sims Freeplay dropped six spots to No. 20. Bejeweled Blitz, EA’s third-biggest mobile game, fell out of the top 20 completely.

“As a result, EA’s market share was down between 13 percent and 20 percent across [iPhone, iPad, and Google Play],” wrote Creutz.

EA Mobile still has 140 million monthly active players, and the company reported that its smartphone games generated $120 million last quarter. That is up 18 percent over the previous year, but Cowen is looking at the company’s performance this quarter.

While EA’s games are struggling, other mobile publishers are seeing growth. Most notably, developer Glu Mobile has what is probably its biggest hit ever with Kim Kardashian: Hollywood. The studio is now the No. 4 highest-grossing developer on iPhone and No. 10 on Google Play. That’s thanks to the hundreds of thousands of dollars that its new celebrity-fueled game is bringing in each day.

“Kardashian continues to monetize in the top 5 in the U.S. and U.K.,” wrote Creutz.

Glu’s mobile revenues are only going to get stronger as the company recently acquired developer Cie Games, which is responsible for a pair of popular driving games. When combined, Glu and Cie move up from No. 10 on Google Play to No. 4.

Mobile megapublisher King has a new success of its own, and it didn’t even need to rely on a reality-TV star. While the company has yet to release a game that matched Candy Crush Saga’s level of revenues, its Bubble Witch Saga 2 is still performing well. In July, the bubble-shooting puzzler finished as the No. 12 top-grossing app on iOS and No. 7 on Google Play.

“King now has four top-20 grossing games across iOS and Google Play, [which is] tops among all developers,” wrote Creutz. “That includes four top-10 highest-grossing games on Google Play.”

King frightened investors following its initial public offering in March. The stock debuted at $22.50 and immediately dropped to around $16 because most people believe the developer will never make another game as lucrative as Candy Crush Saga. In its defense, the studio said it would focus on releasing a larger stable of games that perform well — even if they don’t match the unbelieveable Candy Crush. That’s what the company has with Farm Heroes Saga, Pet Rescue Saga, and Bubble Witch Saga 2.

Finally, developer Blizzard’s free-to-play card battler Hearthstone is back up in the top 20 in July. The game, which isn’t on iPhone or Google Play yet, reached No. 19 on the iPad top-grossing charts. That’s largely due to the new single-player content that Blizzard started doling out last month, the Curse of Naxxramas adventure.

Analyst Arvind Bhatia of Sterne Agee thinks the game is well established to make money for a long time on mobile.

“Hearthstone continues to show steady growth in revenue,” wrote Bhatia. “And that growth should continue for the foreseeable future as it launches on additional platforms like iPhone and Android, as well as new countries.”

It’s still fairly early for Hearthstone, and the game will likely have a very high earning ceiling. Blizzard has already localized the game for major markets like South Korea and China, but it has yet to release a Japanese-language version. That region spends more money than any other on mobile games, and if it adopts Hearthstone, it could push the game over the top.

Returning to EA Mobile, that company could see a resurgence thanks to new content for its smartphone games. The company told GamesBeat that it is working on an update for The Simpsons, and it just released a cooking-themed add-on for The Sims Freeplay yesterday. New content like that usually is enough to get long-time fans to return.