In most cases, Twitter is no longer available as it was originally intended to be used as a text message.
Last week, Twitter turned off the ability to receive SMS messages containing the text of the new tweet. This feature has been disabled for all features except "some countries" that use this feature.
It doesn't help much for the majority of Twitter users who access the service through apps or websites. However, there are still complaints from some people who use SMS to read tweets. One business called DansDeals said it relies on this feature to inform its readers of sales.
This change means that Twitter's era is over. It was built around SMS when the service started. Originally, the 140 character limit was adjusted to the size of the text message, and I was able to send and receive entirely new tweets via SMS. But it's not the main way to use Twitter for a long time, as more people can buy smartphones and use mobile apps.
Twitter has disabled the ability to compose tweets via text in September due to security concerns. The hacker had access to the phone number of Twitter CEO Jack Dorsey, and at this point he could use the SMS feature to tweet from his account. Twitter prevented you from sending tweets via SMS except for "a few regions".
According to a Twitter spokesperson, this latest update will help people "keep their accounts safe." I'm not sure what the risks are when receiving tweets, not when sending them, but Twitter was interested in abolishing this feature for a while. If people get tweets via SMS, they can't show ads, so it's much better for people to check the app.
"We pulled the rest of Twitter through the SMS feature, except for a few countries that depend on it to use it," a spokeswoman for Twitter said. Twitter still sends “important SMS messages” for account security, such as verification codes.