Casual:
* In the loop: This implies being aware of recent developments.
* In the know: Similar to "in the loop," it suggests having access to the latest information.
* On top of things: This indicates being organized and managing current affairs effectively.
* With the times: This suggests being current and aware of modern trends.
* On fleek: This is a more informal term for "perfect" or "on point," which can be used to describe something being up-to-date and stylish.
Informal:
* Up to speed: This implies being knowledgeable about the latest happenings.
* Current: This is a simple and direct way to convey being up to date.
* Fresh: This can be used to describe something that is new or trendy, and therefore up-to-date.
* Modern: This indicates being relevant to the current time.
More informal:
* Lit: This is a slang term for "excellent" or "amazing," and can be used to describe something being up-to-date and exciting.
* On point: This implies being accurate, relevant, and timely.
The best slang term to use depends on the specific situation and your audience.