The creators of Telega, an unofficial Telegram client, have filed a complaint with Russia’s Federal Antimonopoly Service over the removal of their app from the App Store.

“We are facing a situation in which the app has been removed from the App Store, the developer account has been blocked, and the launch of already-installed apps on iOS has been restricted,” the Telega developers said.

Over two weeks, the developers said, Apple provided no “specific reasons or technical findings” to explain the removal. The app’s creators say they could have clarified their position but were “simply not given any specifics.”

The developers are asking the Federal Antimonopoly Service to “evaluate Apple’s actions.” “We believe our app should be returned to the App Store, and Apple’s procedures should change so that other developers do not face such arbitrary treatment,” they said.

The developers of the unofficial Telegram client also threatened to file lawsuits against media outlets and bloggers who, in their view, are spreading false information damaging to their reputation.

Telega gained popularity in Russia after Telegram was blocked. On April 9, the Telega messenger disappeared from the App Store. No official reason was given. The Russian Telegram news channel Ostorozhno Novosti reported that the likely cause was the revocation of security certificates, and that the hosting provider Cloudflare had flagged two domains associated with Telega as spyware. In mid-April, iPhone users began receiving warnings that Telega “contains malicious code.”

IT experts believe that Telega is connected to the Russian social media company VK. It also emerged that the app accesses users’ personal data and intercepts traffic, meaning it can monitor who is communicating with whom, and when.