Google publicly disclosed its acquisition of homework helper app Socratic in an announcement this week, detailing the added support for the company’s AI technology and its relaunch on iOS. The acquisition apparently flew under the radar — Google says it bought the app last year.

According to one founder’s LinkedIn update, that was in March 2018. Google declined to comment when asked for specifics about the acquisition.

Socratic was founded in 2013 by Chris Pedregal and Shreyans Bhansali with the goal of creating a community that made learning accessible to all students.

Initially, the app offered a Quora-like Q&A platform where students could ask questions that were answered by experts. By the time Socratic raised $6 million in Series A funding back in 2015, its community had grown to around 500,000 students. The company later evolved to focus less on connecting users and more on utility.

It included a feature to take a photo of a homework question in order to get instant explanations through the mobile app launched in 2015. This is similar to many other apps in the space, like Photomath, Mathway, DoYourMath and others.

However, Socratic isn’t just a math helper — it can also tackle subjects like science, literature, social studies and more.

In February 2018, Socratic announced it would remove the app’s social features. That June, the company said it was closing its Q&A website to user contributions. This decision was met with some backlash from disappointed users.

Socratic explained the app and website were different products, and it was strategically choosing to focus on the former.

“We, as anyone, are bound by the constraints of reality—you just can’t do everything—which means making decisions and tradeoffs where necessary. This one is particularly painful,” wrote Community Lead Becca McArthur at the time.

That strategy, apparently, was to make Socratic a Google AI-powered product. According to Google’s blog post penned by Bhansali — now the engineering manager at Socratic — the updated iOS app uses AI technology to help users.

The new version of the iOS app still allows you to snap a photo to get answers, or you can speak your question.

For example, if a student takes a photo from a classroom handout or asks a question like “what’s the difference between distance and displacement?,” Socratic will return a top match, followed by explainers, a Q&A section and even related YouTube videos and web links. It’s almost like a custom search engine just for your homework questions.

Google also says it has built and trained algorithms that can analyze the student’s question, then identify the underlying concepts in order to point users to these resources. For students who need even more help, the app can break down the concepts into smaller, easy-to-understand lessons.

In addition, the app includes subject guides on more than 1,000 higher education and high school topics, developed with help from educators. The study guides can help students prepare for tests or just better learn a particular concept.

“In building educational resources for teachers and students, we’ve spent a lot of time talking to them about challenges they face and how we can help,” writes Bhansali. “We’ve heard that students often get ‘stuck’ while studying. When they have questions in the classroom, a teacher can quickly clarify—but it’s frustrating for students who spend hours trying to find answers while studying on their own,” he says.

This is where Socratic will help.

That said, the acquisition could help Google in other ways, too. In addition to its primary focus as a homework helper, the acquisition could aid Google Assistant technology across platforms, as the virtual assistant could learn to answer more complex questions that Google’s Knowledge Graph didn’t already include.

The relaunched, AI-powered version of Socratic by Google arrived on Thursday on iOS, where it also discloses through the app update text the app is now owned by Google.

The Android version of the app will launch this fall.

Updated, 8/16/19, 3:30 PM ET to note Google’s decline to comment.