Joy Ventures recently invested in Doppel, which has developed a unique bracelet that induces calm and focus. Interview with CEO and Co-Founder Dr. Fotini Markopoulou on the inspiration for Doppel, the partnership with Joy Ventures and the difference between Silicon Valley and a human-focused approach to emotional tech products.
Doppel is a wrist wearable that creates a silent vibration which feels like the ‘lub-dub’ of a heartbeat. Certain slower rhythms on the device have been shown to significantly reduce stress, while faster rhythms increase alertness.
Fotini founded Doppel in 2014 with three co-founders from the fields of product design, engineering and electronics, Jack Hooper, Nell Bennet and Andreas Biliki. They were joined by Chief Scientist Professor Manos Tsakiris, an expert on the neurocognitive mechanisms that shape the experience of self-identity. Two of Doppel’s four founders are women and the team is proud of having been selected best Female-Led Investment at the UKBAA Angel Investment Awards.
The wearables market is taking off in impressive fashion, and is predicted to reach $52B in 2020. For products to stand out in this market they must be both effective and pleasing. This marriage of science and design is personified in Doppel’s CEO and Co-founder Dr. Fotini Markopoulou, a physicist and daughter of sculptors who has always been drawn to both science and design. “After 15 years as an academic focusing on quantum physics, I missed the ‘making’ of something,” says Fotini. “In scientific studies we see that it is possible to change people’s perception of themselves, a ‘plasticity of the self’. This opens up an amazing opportunity for technology to play a role and help us achieve the state of mind we want. We wanted to make products that use science and technology to help people live better.”

The science behind Doppel is founded on interoception, a scientific arena that studies the way a person’s perception of what is happening inside the body is able to influence our emotions and cognition. Doppel is described by Fotini as interfacing with the body as a kind of emotional second skin.
The heartbeat is the most fundamental biological rhythm, with us from the womb, and Doppel enables us to harness it to help us achieve the emotional state we strive for at any given time,” explains Fotini.
As the mother of a three year old child in the first stages of the product’s prototype, Fotini admits she used Doppel as a ‘replacement for coffee’ after sleepless nights, but today most users employ Doppel to induce calm. 2500 units of Doppel have already been sold online, and the testimonials on the website tell personal stories of the product’s benefits.
The collaboration with Joy Ventures was a very natural fit. “Doppel’s founding team has a vision that aligns perfectly with Joy’s vision and DNA. We are thrilled to join this excellent team on their product development journey,” says Miri Polachek, CEO of Joy Ventures. “Beyond the financial investment, the Joy team is working closely with the Doppel team to support their scientific studies aimed at further proving the product’s efficacy.”
Working with Israeli experts in neuroscience and product development was one of the factors that drew the Doppel team to partner with Joy. The team recently returned from a visit to Tel Aviv and plans many more trips in the future. The experts who will help Doppel conduct further product research include Dr. Nava Levit-Binnun who founded and runs the Sagol Center for Brain and Mind at the School of Psychology at the IDC Herzeliya, Dr. Yulia Golland, a leading researcher at Nava’s lab with extensive expertise in physiological signals and Dr. Mor Nahum of the Hebrew University of Jerusalem.
After engaging with the investor community in Silicon Valley, Fotini was particularly drawn to Joy Ventures’ human-centered approach: “Silicon Valley is populated mainly by people coming from programming backgrounds who are most excited by technology. I got the sense that they are almost looking to make people into computers. When we met the Joy team it felt like something completely different.”
According to Fotini, the rise of wearables and emotional wellbeing apps brings with it particular challenges. “We actually see that sleep apps can exacerbate peoples’ insomnia. The attempt to hijack reward systems often ultimately backfires. Joy’s ethical, human-focused approach to emotional wellbeing technology is exactly where we’re coming from as well, so they are the perfect partner for Doppel,” concludes Fotini.