Humans and their furry companions share a unique bond and encounter a range of similar health concerns. Despite thousands of households worldwide welcoming pets, there is still an absence of integrated health monitoring systems jointly addressing the well-being of both [1]. Quality of life (QoL), both physical and mental, as well as perspectives on health, well-being, safeguarding, and environmental factors, require holistic and interdisciplinary approaches. In this context, QoL as defined by the WHOQOL framework, encompasses physical, psychological, social, and environmental dimensions [2]. Wearables and connected technologies extend QoL assessment beyond episodic encounters to continuous, context-aware monitoring of sleep, mobility, and participation. In human-companion-animal ecosystems, shared environments and daily routines link animal welfare directly to human QoL, enabling earlier detection of decline and more targeted interventions. These approaches emphasize the interconnected relationship between humans, animals, and the environment [3]. Three influential concepts of One Health, EcoHealth, and Planetary Health, illustrate this linkage. Although they share foundational elements and conceptual similarities, they differ in their focus and scope [4]. One Health aims to improve well-being by preventing risks and mitigating crises at the human-animal-environment interface and emphasizes a whole-of-society approach [5, 6]. EcoHealth extends this perspective by explicitly integrating environmental sustainability and socioeconomic stability [7]. Planetary Health, while less interdisciplinary, concentrates primarily on human health within environmental boundaries [4]. Despite these differences, all frameworks converge on a central message: human, animal, and environmental health are inseparable, and technological advances must reflect this interconnectedness to achieve meaningful impact.

In 2018, the World Health Organization (WHO) released a comprehensive taxonomy of Digital Health, identifying numerous aspects of this rapidly expanding field [8]. Investments in Digital Health are substantial, for example, reaching $6 billion in 2017 [9], reflecting its potential to enhance healthcare delivery and support public health systems [10]. Digital Health interventions increasingly benefit humans, animals, and ecosystems [11] by leveraging two primary dimensions: (i) real-time big data streams and (ii) wearable and tracking technologies that strengthen disease surveillance, early-warning systems, preparedness, and response by integrating traditional surveillance with new data sources [12].

The One Digital Health (ODH) concept bridges the gap between holistic health approaches and technological advancements [13]. ODH defines the components of the digital health ecosystem and explores how emerging technologies can support healthcare delivery and promote overall well-being across species. A central aspect of ODH is the integration of human and veterinary medical data into real-time information systems, an essential step in advancing public health, particularly where human and animal environments intersect. Historically, healthcare was delivered in a largely paternalistic manner (Healthcare 1.0); With the implementation of wearable devices, the paradigm shifted to reactive care (Healthcare 2.0); Continuous monitoring enabled proactive care (Healthcare 3.0), and is already pushing the field toward predictive care (Healthcare 4.0); By the integration of human and animal health data, we will approach Healthcare 5.0 (Figure 1) [14, 15].

In this viewpoint, we examine the role of wearable technologies across five key areas of (i) management of chronic conditions, (ii) monitoring physical activity, (iii) behavioral and mental health, (iv) early disease detection, and (v) clinical applications. We emphasize ODH contributions to the health of humans and companion animals (specifically dogs and cats) and highlight how interconnected data streams reveal cross-species insights, such as identifying common stressors. We also discuss technical challenges and opportunities in adapting human wearables for animal use. Finally, we outline a roadmap for advancing integrated, cross-species wearable health monitoring systems.

In 2024, 46% of German households (18.45 million homes) host a pet [16], most commonly dogs and cats, followed by small mammals, such as rabbits and guinea pigs, birds, fish, and reptiles [16]. The German pet market increased by €4 billion in two decades to €7.1 billion in 2023 [16]. Pet owners increasingly consider their pets as integral family members [17], showing the importance of pet health, which directly extends to the QoL of owners and the broader community [18, 19], particularly when managing chronically ill pets with conditions like epilepsy, diabetes, allergy, cardiovascular diseases, dementia, and cancer [20]. Pets in poor health often trigger a domino effect, ranging from rising pet health insurance premiums to affecting the well-being of pet owners. Neurological conditions such as epileptic seizures particularly strain owners emotionally, not only because of their episodic nature but also due to medication side effects and clinical signs including ataxia, sedation, and behavioral changes [21, 22].

“We are more alike than we might think.”

Connected Health is a patient-centred model that encompasses wireless, digital, electronic, mobile, and tele-health solutions, in which devices, services, or interventions are designed around patients’ needs and health data are shared to enable proactive and efficient care [37]. Within this paradigm, telemedicine is a core component that enables quicker and more efficient diagnosis and clinical care by bridging physical distances and extending spatial-temporal monitoring [38]. Wearable technologies such as fitness trackers, smart watches, wearable ECG recorders, and smart clothing facilitate real-time, non-invasive monitoring of health parameters (e.g., vital signs) [39, 40]. Offering real-time feedback, wearables are an objective tool and beneficial for the elderly, rehabilitation, and those with disabilities. Furthermore, wearables facilitate home-based rehabilitation and save over $200 billion in healthcare costs by reducing clinician-patient interaction time as well as transportation efforts [41].

Smart devices help managing sleep [42], stress [43], productivity, and chronic diseases [44], detect depression, and monitor activities [45]. Wearables have applications in stroke recovery [46], assessing muscle activity [47], and bear the potential to replace magnetic resonance imaging (MRI) for brain activity monitoring [48]. In chronic conditions like chronic obstructive pulmonary disease (COPD), wireless pulse oximeters enhance self-management and reduce hospital admissions. Apple’s ECG has received Food and Drug Administration (FDA) and European approval, indicating wearables’ growing importance [49]. During the COVID-19 pandemic, wearables aided in remote monitoring and consultations for chronic and post-COVID conditions [50].

The global market in wearables for pets was $2.70 billion in 2023 and is expected to grow by 14.3% from 2024 to 2030 [51]. Wearable devices for companion animals increasingly enable continuous and remote health monitoring, conceptually analogous to human Remote Patient Monitoring Systems (RPMS), although the terminology is not yet standardized in veterinary medicine [52, 53]. Figure 2 provides an overview of the cross-species mapping between biosignals, representative conditions, and major applications. It visualizes the cross-species health ecosystem enabled by wearable technologies through mapping three interconnected layers: application areas (inner ring), target diseases or conditions (middle ring), and the biosignals required to monitor them (outer ring). This structure shows the direct linkage between measurable physiological markers such as heart rate, respiratory rate, glucose, sleep, or movement and specific clinical or behavioral conditions relevant to both humans and companion animals. By organizing these elements around the Healthcare 5.0 framework, the figure illustrates how shared biosignals enable unified approaches to chronic disease management, mental health assessment, physical activity monitoring, clinical care, and disease prevention across species. One of the primary applications is monitoring physical activity. Equipped with accelerometers and GPS, pet devices provide detailed data to support the management of obesity and ensure sufficient exercise [54]. Deviations from normal activity patterns signal underlying health issues. According to Chambers et al., wearable accelerometers accurately quantify the intensity and duration of physical activity in dogs, thereby aiding in weight management and maintaining physical fitness [55]. Wearable technologies further promise to detect and manage chronic conditions in pets. In particular, their applications for monitoring canine epilepsy collect objective data on seizure frequency and duration, which supports more informed and individualized treatment planning [56]. Similarly, Oliveira et al. employ wearable pulse oximeters and heart rate monitors to manage respiratory and cardiovascular conditions [57].

Another application is in the early detection of diseases and health anomalies. Brugarolas et al. explore the use of wearable biosensors in detecting physiological changes correlated to stress, allowing for earlier interventions [58]. Foster et al. demonstrate the feasibility of reconstructing ECG, heart rate, respiration rate, and body movement of dogs during rest and sleep [59]. Moreover, behavioral monitoring using wearable devices detects anxiety, enabling timely behavioral interventions [60]. Similarly, tracking sleep patterns and restlessness in pets provides insights into their mental health and overall well-being [61].

Wearables also support the management of specific health conditions. For example, in diabetic pets, continuous glucose monitoring through wearable devices enables better disease control [62]. These devices assist veterinary surgeons in tracking disease progression and assessing therapeutic outcomes. Engelsman et al. demonstrate effective gait analysis to quantify ataxia in dogs [63].

Transitioning from a subject-to-device paradigm (hospital-centered), where technology is primarily confined to clinical settings, to a device-to-subject (patient-centered) approach has empowered individuals [75] and, increasingly, animals to participate actively in their health management. Wearable devices that continuously monitor environmental, behavioral, physiological, and psychological parameters have facilitated this shift [2]. The seamless integration of data from these devices into electronic health records (EHRs) has accelerated the move from Healthcare 2.0, characterized by data-driven decision making, towards a more proactive Healthcare 3.0. Other important technologies used in this revolution are big data analytics, block-chain technologies, artificial intelligence (AI), edge computing, and wearables powered by the Internet of Things (IoT) [76].

Precision prevention [77, 78] as a key component of Healthcare 4.0 relies on detailed personal and, now, even animal health information to tailor interventions. Wearable devices provide granular data on both human and animal health status, facilitate the identification of at-risk populations, and support preventive measures. By collecting data from humans and animals on a large scale, these devices contribute to public health surveillance and the early detection of emerging threats, including zoonotic diseases. The COVID-19 pandemic highlighted the critical role of wearable technology in tracking disease spread and informing public health interventions [79].

To realize the full potential of wearable devices in ODH, we also need to address ethical considerations. Establishing robust data governance frameworks and ensuring data protection are essential for building trust among users. We further need to develop standardized data formats and protocols to facilitate interoperable data exchange between different healthcare systems and devices across species. Techniques such as federated learning, differential privacy [80], secure multi-party computation [81], homomorphic encryption [82], and trusted execution environments [83] provide insights from private data while maintaining confidentiality. However, these techniques also face challenges such as communication overhead, system and data heterogeneity, and the need for robust security measures to prevent data leakage and model poisoning. By embracing the power of wearable technology and fostering collaboration between human and animal health sectors, we can create a Healthcare 5.0 future where diseases are anticipated, prevented, and managed more effectively for all living beings.