Quanttus, a startup that has been working since 2012 on a wristworn wearable that offers continuous blood pressure monitoring, launched a blood pressure tracking app this week, called Q Heart.

The app allows users to manually enter blood pressure readings or sync them from Apple’s HealthKit. Users can also enter notes about specific readings, review older readings, and access a chart that shows blood pressure trends. Q Heart can also alert users with blood pressure notifications and reminders.

The company is still working on developing a continuous blood pressure monitoring device, an anonymous former employee told MIT Tech Review, but developing an accurate device is taking longer than Quanttus expected the source said.

The company's official statement to the publication was that they were "still thinking bigger than the app".

Almost a year ago, in April 2015, when Quanttus Cofounder David He spoke at an event, he said Quanttus was already testing a wristworn wearable device that continuously monitors blood pressure. He said at the time that Quanttus hoped to have the device on "thousands of wrists" for testing purposes in the near future.

Quanttus has also experienced some turbulence in the last year. In August 2015, the Boston Globe reported that Quanttus CEO Shahid Azim left the company, but he is still listed on the board. At the time, former employees also said there was a round of layoffs and resignations at the company.

Quanttus has raised at least $22 million to date from Khosla Ventures and Matrix Partners.