Pavel Durov had some sharp words about app stores.Illustration by Alex Castro / The Verge

An upcoming Telegram update has been stuck in Apple’s app review for two weeks “without explanation,” according to a Telegram post from CEO and founder Pavel Durov (via MacRumors). He claims that the update is “about to revolutionize how people express themselves in messaging” but it hasn’t yet been approved.

Durov discussed the unexplained holdup as part of a broader critique of app store business models. He says that Telegram is discouraged by the “obscure” app review process that’s “imposed on all mobile apps by the tech monopolies.” He goes on to say that “If Telegram, one of the top 10 most popular apps globally, is receiving this treatment, one can only imagine the difficulties experienced by smaller app developers.”

A screenshot of Telegram CEO Pavel Durov’s post critiquing the app store model. Screenshot by Jay Peters / The Verge

It’s unclear exactly what’s in the new update, and Apple and Telegram didn’t immediately reply to a request for comment. This isn’t the first time Durov has called out Apple for its app review processes. In 2018, Durov said that Apple had been blocking updates to the Telegram iOS app after Russia banned Telegram. A day after Durov posted about the issue, Apple approved an update.

Telegram recently rolled out its $4.99 per month Premium subscription, which gives users access to larger uploads, faster downloads, a voice-to-text feature, unique emoji reactions, and more.