Discord is amping up its restrictions on adult content, with new-age gates on NSFW servers and a ban on accessing these servers from iOS devices.

Entire servers can now be marked as NSFW if their community “is organized around NSFW themes or if the majority of the server’s content is 18+.” This label will be a requirement in the future, and Discord will proactively mark servers as NSFW if they fail to self-identify. Discord previously allowed individual channels to be marked as NSFW and age-gated.

The NSFW marker does two things. First, it prevents anyone under the age of 18 from joining. But the more significant limitation is that it contains NSFW servers from being accessed on iOS devices — a considerable restriction that’s almost certainly meant to cater to Apple’s strict and often prudish rules around nudity in services distributed through the App Store. Tumblr infamously wiped porn from its entire platform to come into compliance with Apple’s restrictions.

At least some Discord users seem to be frustrated by the changes, judging by the reaction on Twitter. Several people tweeted that this could make them switch to Android. One said the restriction posed a problem for them since they needed to monitor their server while mobile. The ban seems to be particularly concerning to art communities that include sexual illustrations.