Bluesky isn’t the only company leaning into AI to help build custom feeds, it seems. Amid a slate of recent product releases, X this week announced the launch of Grok-powered Custom Timelines, which let you dive into one of over 75 specific topics through curated feeds that can be pinned to your home tab.

The company touted the feature as one of the “biggest changes” to the app to date, saying it uses Grok’s AI to not only build these custom timelines but also personalize them for individual users.

The custom feeds are arriving at the same time as X has announced it is shutting down X Communities, a feature that had allowed people to create their own member-based communities around various topics, but saw declining use.

On X, the company’s head of product, Nikita Bier, noted that the custom timelines work even better for topics you already engage with. A rep for X explained to TechCrunch that the custom timelines aren’t based on traditional signals like keywords or hashtags. Instead, the company said, Grok reads every post, understands it, and then adds topic labels. This is made possible by the AI models from Grok owner xAI, the company that acquired X last year, tying the two services even closer together.

At launch, the custom timelines are available only to Premium subscribers on iOS. Android support is in the works. All Premium subscription tiers can access this feature.

Image Credits:screenshot from X

To use the feature, simply scroll to the right past your “For You” and “Following” feeds on X, as well as any other personal lists you may have pinned. Then tap the plus ( + ) sign to choose which custom timelines you want to pin to your home tab. (Choose wisely, because you can only pin up to 10 topics or lists!)

You can also reorder your selected topics from the same screen.

Image Credits:screenshot from X

Once pinned, you can tap on any of the feeds from your home tab across platforms to browse your pinned custom feeds.

Notably, the second position in each feed was filled by an ad — which suggests X just found a way to increase its ad inventory. That matters: X’s ad business has reportedly been struggling since Musk’s acquisition, with conflicting reports about whether things have improved.

X’s custom timelines offer 75+ category options

The initial topics are broad and fairly standard — high-level categories similar to the type of sections you might find on news sites. These include subjects like Business & Finance, Sports, Technology, Politics, Stocks & Economy, News, Science, Movies & TV, Food & Drink, Art, Real Estate, Home & Garden, Beauty, Education, Gaming, and others.

Beyond the broader sports category, there are also options for following specific sports, including American football, baseball, basketball, boxing, soccer, golf, MMA & wrestling, racing & motorsports, rugby, snow sports, ice hockey, tennis, cricket, Formula 1, cycling, and the Olympics. (Oh, and esports, if you want to count that.)

Pop culture and tech topics also make up many of the available categories, with the former allowing you to pin topics like celebs, music, concerts, country music, dance, electronic music, fashion, pop, K-pop, J-pop, podcasts, hip-hop, and jazz.

Alongside the Technology category, you can also follow special interests like Artificial Intelligence and Cryptocurrency — two perennially popular topics on X. There are also categories for things that overlap with Elon Musk’s various businesses and interests, like robotics, software development, space, and biotech.

Image Credits:screenshot from X

Other general categories include things like anime, digital art, photography, career, pets, design, marriage & family, shopping, mental health, and more.

News categories: War, crime, and elections

Worth flagging: The initial set of news-related topics leads with the Iran conflict, crime, and elections at the top of suggestions.

While this likely reflects the current conversations taking place on X, it’s also an example of how a product decision can influence what news people see. A cleaner solution might be to organize the dozens of options into larger high-level categories listed in alphabetical order, with the subcategories appearing when you tap each. That would allow X to greatly expand its “news” categories beyond these big three.

There could also be concern about these timelines being built by Grok, which was ostensibly created to be politically neutral and “truth-seeking,” but in practice has often skewed right or amplified misinformation.

In our own testing though, the custom timelines did not seem to lean obviously right or left. In a handful of test scrolls, the feeds drew from a range of outlets like ABC, CBS, CSPAN, AP, Reuters, AFP, Daily Beast, The Hill, Foreign Policy, Puck, The Atlantic, The Economist, Bloomberg, Al Jazeera, Forbes, and the BBC (not all of which I follow), alongside commentary from various pundits.

Whether these custom feeds will dramatically change how people use X remains to be seen.

For the most part, people tend to want to see the things they care about appear in their main algorithmic feed. But the custom feeds do allow for exploring new interests or dipping into topics only when they’re relevant — like pulling up a sports feed when the game is on. Combined with X’s new “Snooze Topics” option for the For You feed, you can more precisely tailor your X to your liking.