Getting a lot of articles in the tech press, genuinely open source “twitter” type system without ads/data tracking and currently with more users than I’d expected and less fools!
Sign up with one of these : https://instances.mastodon.xyz/
The main one mastodon.social is overloaded and not accepting more users but just pick one that is multi user and near to your country. Use the “federated timeline” to see the “toots” (which is what they call “tweets” from people on other servers).
You get 500 characters and can also add multiple pictures – its a lot like Usenet with a better UI and before the idiots took it over!