Yes, lots:
-The official website interface has an alternative Tweetdeck-style multicoloumn interface (more info: https://fedi.tips/how-to-activate-mastodons-tweetdeck-style-advanced-web-interface/)
-Elk is a third party web interface (more info: https://elk.zone/)
-Sengi is a popular third party desktop app (more info: https://nicolasconstant.github.io/sengi/)
-Buffer is a commercial service that lets you crosspost between social media including Mastodon (more info: https://buffer.com/)
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