As pointed out by The Mac Observer, the Audible app is no longer available to download in the Chinese App Store. The change was first reported by Apple Censorship, which listed the app as having been removed on Thursday.

For those who aren’t familiar, Audible is an online audiobook and podcast service owned by Amazon, that allows users to purchase and stream audiobooks and other forms of spoken word content.

The Mac Observer has reached out to Apple, Audible, and Amazon to try and ascertain why the app is no longer available. No response had been received by any of the company’s at the time of this writing.

While the exact reason is not yet known, it is being speculated that the app may have been removed following some changes to the app by its developers, or it may just be a request from the Chinese government complied with by Apple.

If the cause turns out to be the latter, it would be a very serious situation for both Apple and Amazon.