Citigroup announced today that it will release a mobile banking app for the Apple Watch on April 24, the day the watch enters the marketplace.

Citi’s app is currently the only bank app for the Apple Watch, though Mint and an app called Invoice2go are also available. Moven also has an Apple Watch app in the works.

The app, called Citi Mobile Lite, will display balances and give information about recent transactions. It will also send real-time notifications of credit card transactions.

The app does not seem to have an ATM locator, which is one of the most commonly used mobile banking features, but could be a challenge on such a small screen. It also does not feature payment alerts, despite the language on Apple’s site, featured at right here.

Citibank was the first major bank to offer a feature displaying balance outside the logged-in app, which it calls Mobile Snapshot. This feature was essentially ported to the watch, which does not require logging in either.

“We were very excited to be able to be able to leverage the product set [from Citi’s 2014 mobile app refresh] for the Apple Watch,” Heather Cox, chief client experience, digital and marketing officer for global consumer banking at Citigroup told Bank Innovation today.

The app was developed in about 120 days, she said. It is tethered to the phone, and operates intelligently in concert with it — the watch receives alerts when the phone is sleeping, for example.

“We decided to keep it super simple, waiting to see exactly how it will be used. That’s why we call it Mobile Lite,” Cox said. “We look at it as a new way to engage with our clients in their daily lives. It’s a way to get them relevant data faster and help them use their money wisely.”

Cox admitted no one knows exactly how wearables will play out in banking or beyond.

“Who knew when the iPhone came out in 2007 that it would become our constant companion?” she said. With the Apple Watch, she said, Citi is “excited to learn along with our customers” how it will be used.