Story highlights Apple bans app that helps users find other apps for free

AppGratis says it has 12 million users on Apple's mobile system

Apple said AppGratis mimics its App Store's functions

Sources say episode is part of a new wave of app crackdowns by Apple

An app that helps users find other apps for free has been banned from Apple's mobile store in a move some say heralds a new round of blacklisting for content the company doesn't like.

AppGratis , which partners with app developers as a sort of clearinghouse to help them get noticed, was first informed Friday that it was being pulled, according to CEO Simon Dawlat. The app disappeared from the App Store on Sunday.

Dawlat said he'd been on a plane to Brazil and arrived to discover more than 75 missed phone calls and "a seemingly unlimited flow" of text messages.

"I immediately thought that someone in my family had passed away during my flight and couldn't touch my phone for a few minutes," Dawlat wrote in a blog post . "Scared. Paralyzed. Trying to imagine what the terrible news could be."

Apple said the app, created in 2008, was pulled for violating a pair of its developer guidelines -- one that bars displaying apps for purchase "in a manner similar to or confusing with the App Store" and another that bans push notifications that contain advertising or "marketing of any kind."

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Dawlat said that Apple had approved an iPad version of the app, which has roughly 12 million iOS users, just a week before the apps were banned.

Apple did not immediately respond Wednesday to a request for additional comment.

Dawlat said the company has addressed the App Store issue before, apparently arguing successfully that AppGratis isn't similar to Apple's closely policed sales environment. As far as push notifications, he said the app sends one a day, saying "today's deal is here," and that users can opt out of getting it.

Talking to an Apple contact didn't make it any clearer, he wrote.

"I asked how he and his team could have possibly changed their minds overnight, pretty much pulling the plug on a 45-person company," Dawlat said. "He seemed very detached regarding the gravity of the situation, and was unable to let me know on what specifics these decisions had been made."

Dawlat questioned why similar apps hadn't been banned. According to at least one report, it might not be long.

Wall Street Journal's All Things D blog reported that the ban was the first step in a new wave crackdowns by Apple on "app-discovery" apps.

Citing "sources familiar with Apple's thinking," the report said Apple thinks those apps "threaten the legitimacy of the App Store" by letting developers pay their way to a high ranking.

Apple famously keeps tight controls on its App Store, not allowing any app in without prior approval. The company argues it's a quality-control issue that keeps out sub-standard content. Many critics prefer a more open-ended approach like Google's Play Store for Android devices, which give developers significantly more leeway.

Dawlat said AppGratis will continue to be updated for people who have already downloaded it and that he'll keep trying to work with Apple to find a solution.