After founding and selling the popular Mastodon client Mammoth, developer Shihab Mehboob is returning to compete with it with the launch of his new app, Saturn. Not to be confused with the social calendar of the same name, Mehboob’s Saturn works with the decentralized social network Mastodon and specifically offers a unique “Highlights” feature that summarizes your timeline and shows popular content.

Mehboob stresses that the app is not leveraging AI or even machine learning to accomplish this, noting that many in the Mastodon community are wary of such technology. Instead, he says that the Highlights feature is powered by a simple native checker that looks to see which posts and accounts from the user’s timeline are seeing the highest likes and reposts and brings those forward in the app. However, the feature doesn’t necessarily include only content from accounts you follow, because it also supports content that was reposted into your feed.

In this way, Saturn aims to address critics’ complaints about using the would-be Twitter/X alternative, Mastodon, where it can often be hard to find interesting accounts to follow when you first join.

Saturn also supports expected features like the ability to post images, videos, GIFs, polls, custom emoticons, drawings, spoiler text, and more.

Unlike X and Meta’s Threads, which rely on algorithms to curate content for the individual user, Saturn promises chronological timelines only.

Similar to other third-party Mastodon apps, like Ivory, you can configure Saturn’s bottom navigation bar to include quick access to things like popular posts, the latest news, suggested accounts, communities, and trending tags. You are also able to easily access your feed, the firehose from your Mastodon server, community posts, and lists, as well as your bookmarks and profile from the in-app nav bar.

In addition, the app won’t include ads as it instead relies on premium subscriptions to sustain itself. For $12.99 per year (or $39.99 as a one-time purchase), Saturn’s subscription offers access to the smart highlights discovery feature, and other options, including a lurker mode for browsing timelines safely without accidentally liking something (Instagram, TAKE NOTE!), a speed dial for messaging your regular contacts, support for unlimited accounts, push notifications, custom themes and icons, social sharing, shortcuts, widgets, and more.

With a focus on iOS 18, Saturn also supports Apple’s App Intents (for Shortcuts), Control Center Widgets, Translations, Pencil gestures, and Live Activities for the Apple Watch. (The Watch app is included with the app download.)

Mehboob says he was able to launch Saturn as it has been more than a year since the sale of Mammoth, which is now backed by Mozilla, Long Journey Ventures, and Salesforce’s Marc Benioff.

“I find that the biggest draw with Saturn is its beautiful interface, customization, smoothness, and the ability to add in new OS-specific features fast,” Mehboob says. “It looks and feels right at home on iOS,” he adds.

The app is a free download and offers in-app purchases.