Apple's newest gadget has a shipping date.

During Apple's first quarter earnings call, on Tuesday, CEO Tim Cook gave the most specific timeline for the connected wristwatch. "Development for Apple Watch is right on schedule, and we expect to begin shipping in April," he said. Apple had said the device would land in early 2015 when it was unveiled in September.

The other device introduced then, the iPhone 6, did quite well for the company. Apple posted a record-shattering holiday quarter, shipping 74.5 million iPhones and netting $74.6 billion in revenue, a 30% annual increase. Sales in China, which grew 70% year on year, drove much of the quarter's success. Apple debuted its first ad for the Watch in China.

A delay in Apple Watch shipments came from the need to tweak the software, including the app notifications and "information summaries" Apple calls "glances," Mr. Cook said. The company has not disclosed where the device will be sold outside of Apple Stores.

Mr. Cook remains enthusaistic about the device. "I'm using it every day and love it and can't live without it," he said on the call.