The порно звезд порнографииmenstrual app space is crowded, but one company is setting itself apart with new funding.

Clue, the period and ovulation tracker, raised $20 million in a Series B round announced on Wednesday.

The round was led by Nokia Growth Partners with participation from Union Square Ventures, Mosaic Ventures and other investors. Union Square Ventures and Mosaic Ventures led Clue's $7 million Series A round in 2015.

The influx of money brings the Berlin-based company's total funding up to $30 million since its launch in 2013.

“I feel as strongly as ever that Clue’s mission is to keep female health and its advancement at the top of the global agenda and I am thrilled to partner with a prestigious circle of investors who share our vision," Clue CEO Ida Tin said in a statement. "Healthcare is already going digital, just look at the 60 percent of smartphone users in the U.S. using their devices to manage health. Female health is also driving this. And when you consider that more than half of the world’s population is female, you realize how enormous the market potential and opportunity for Femtech companies is to truly make an impact."

Clue is one of several period-tracking apps, but while many of the free options are simple calendars with options to note sexual activity or symptoms like cramps, Clue is slightly more complex.

The app allows users to track periods, PMS symptoms, fertility and moods. It also includes tracking information for basal body temperature and sends alerts about an upcoming fertility window or when a period is expected to arrive. Most other apps are more focused on tracking periods.

The app aims to educate, asking users basic questions about their menstrual cycle and offering context and definitions about the normal length of a period or PMS, for example. Users can invite others to track or view their cycles as well.

The free iOS and Android app comes in several languages and can be linked to the Apple Watch.

Clue is part of a field of apps and wearables women are using for both birth control and fertility.

Clue will use its new round of funding to expand its team, market to new users and further develop its app, the company said.