In Short: Twitter has just announced that 'Moments' will no longer be available on Android and iOS. The company is not removing this feature completely, though, as you'll still be able to use it from the web, but it won't be available on mobile platforms any longer. This will go into effect on October 23, says the company. This does come as a surprise, as Twitter did not give out any indication that it may remove the feature for mobile platforms, quite the contrary, the company said that it will continue improving it, and that announcement came only a couple of months ago, something obviously changed in the meantime. As a reason for this move, Twitter basically says that users are not as interested in moments on mobile platforms, saying that they usually remove features if they're not used often, so that the company can focus on providing products / features that users will care about more.
Background: Starting on October 23, you will no longer be able to create new 'Moments' on Twitter for Android and iOS, but you will be able to access existing ones, in case you were wondering. Moments, for those of you who do not know, provide Twitter users with a collection of tweets and media content specially curated around a specific topic, and it actually seemed like a really decent feature back when it was launched, but it seems like users are far less interested than Twitter hoped they would be.
Impact: The company did not really share any usage statistics when it comes to Moments, so we cannot really say if this move is justified or not, but there you have it. It remains to be seen if Twitter plans to replace moments with something similar on mobile, or will it simply move on and try with a completely different feature, though the latter is more probable.