A comprehensive human factors validation study was conducted to evaluate the effectiveness of the IKE Bluetooth Low Energy (BLE) System in age-gating and controlling an Electronic Nicotine Delivery System (ENDS) device. This study assessed the IKE application user interface, mitigated potential use-related hazards through observational analysis of participants interacting with the IKE application and a test device, and evaluated participant feedback. The IKE BLE System, integrated on a System-on-Chip (SoC) with an interactive on-market user interface, was tested in simulated-use environments with representative user populations. Results indicate high efficacy in age verification, with 100% of participants successfully completing the process, though challenges in device deactivation post-idle time were identified. These findings are under review by the U.S. Food and Drug Administration (FDA) as part of a Pre-Market Tobacco Application (PMTA) for the IKE BLE System on a Chip.

Introduction

The IKE BLE System is designed to restrict access to ENDS devices by implementing robust age-gating mechanisms, a critical public health measure to prevent youth initiation of nicotine use. This study aimed to validate the system’s effectiveness in age verification and device control through a human factors approach, focusing on the usability of the IKE application and its Bluetooth chip functionality. The system leverages smartphone technology to connect to and activate an ENDS device, ensuring only age-verified users can operate it. This study evaluates the system’s performance in simulated-use scenarios, addressing legal age connectivity, device activation, and deactivation protocols, including biometric authentication and idle-time deactivation.

Methods

A multi-center human factors validation study was conducted with a sample of 102 participants recruited from the general population. Participants were 51% male and 49% female, aged 18 to 67 years (22% aged 18–20, 18% aged 21–24, 20% aged 25–44, 20% aged 45–64, and 20% aged 65 or older). Inclusion criteria required participants to be comfortable using smartphones and phone applications, as assessed by a 5-point Likert scale intake questionnaire (mean score ≥ 4.0). Participants were tasked with using their own smartphones to work through a series of tasks designed to simulate real-world usage of the IKE BLE System. The study protocol involved three primary tasks: (1) downloading and installing the IKE application, (2) completing age verification using on-screen prompts, and (3) activating and deactivating a test ENDS device via Bluetooth connectivity. Device activation was assessed by the ability to establish a stable Bluetooth connection, while deactivation was evaluated by the system’s ability to disconnect the device after 15 minutes of idle time or through biometric re-authentication (fingerprint or facial recognition). Observational data were collected on task completion rates, error occurrences, and user-reported ease of use. Participants rated their experience using a 5-point Likert scale (1 = Not Easy, 5 = Extremely Easy). Data were analyzed using descriptive statistics and qualitative thematic analysis of participant feedback.

Results

Of the 102 participants, 101 (99%) successfully downloaded the IKE application, with one participant unable to complete the task due to smartphone compatibility issues. All participants (n=101) who downloaded the application successfully completed the age verification process, achieving a 100% success rate. Age verification was conducted through a third-party service integrated into the IKE application, ensuring compliance with legal age requirements (21 years or older in the U.S.). Device activation via Bluetooth was achieved by 100% of participants who completed age verification. However, the system’s automatic deactivation feature after 15 minutes of idle time or loss of Bluetooth signal was less reliable, with 15% of participants reporting failure to deactivate the device under these conditions. Biometric re-authentication, required to reactivate the device after idle periods, was successfully completed by 98% of participants, with two participants experiencing issues due to poor fingerprint recognition. Participant feedback on ease of use was generally positive, with 74% rating the application as “Extremely Easy” (score = 5), 16% as “Very Easy” (score = 4), 8% as “Somewhat Easy” (score = 3), 1% as “Not Very Easy” (score = 2), and 1% as “Not Easy at All” (score = 1). When stratified by age, race/ethnicity, and gender, no significant differences in usability ratings were observed (p > 0.05, chi-square test). However, participants aged 65 and older reported slightly lower confidence in navigating the application (mean score = 4.2) compared to younger cohorts (mean score = 4.8). Thematic analysis of feedback highlighted recurring concerns about the reliability of Bluetooth connectivity and the clarity of instructions for biometric re-authentication.

Discussion

The IKE BLE System demonstrates high efficacy in age-gating, with a 100% success rate in age verification, aligning with regulatory requirements to restrict ENDS access to legal-age users. The system’s integration with smartphone technology and third-party age verification services ensures robust access control, a critical feature for preventing youth initiation of nicotine products. Biometric re-authentication, while effective for 98% of participants, revealed limitations in fingerprint recognition for a small subset of users, potentially due to environmental factors (e.g., lighting, skin condition) or hardware variability. Future iterations of the IKE BLE System should explore multimodal biometric options (e.g., combining facial recognition and voice authentication) to enhance reliability across diverse user populations. Participant feedback underscores the importance of user-centered design in health technology applications. While the majority found the IKE application intuitive, the lower confidence among older adults suggests a need for age-specific usability enhancements, such as larger font sizes, simplified navigation, and more explicit instructions. The lack of significant differences in usability across race/ethnicity and gender indicates broad accessibility, though larger sample sizes are needed to confirm these findings.

Implications and Future Directions

The results of this study will be included as part of a PMTA for the IKE BLE System on a Chip. The system’s potential to eliminate youth access to ENDS devices addresses a critical public health concern, as youth vaping remains a significant challenge. However, the IKE BLE System’s reliance on Bluetooth connectivity and smartphone compatibility introduces potential barriers, particularly for users with older devices or limited technological literacy. Future research should focus on improving device deactivation reliability, enhancing biometric authentication, and developing alternative access methods for users without compatible smartphones. IKE is currently refining the system’s software to address the identified issues, including improved Bluetooth stability and more robust idle-time detection. The company has also implemented a rigorous software development program, incorporating user feedback to optimize the application’s usability. An expedited FDA review is anticipated, which will determine the system’s approvability for market entry.

Conclusion

The IKE BLE System offers a promising solution for age-gating and controlling ENDS devices, with high efficacy in age verification and device activation. However, challenges in automatic deactivation and biometric re-authentication highlight areas for improvement. These findings contribute to the growing body of evidence on technology-driven solutions for tobacco harm reduction, emphasizing the need for rigorous human factors validation to ensure safety and accessibility for all users.

Funding and Acknowledgements

This study was funded by IKE Tech LLC. The authors acknowledge the contributions of the study participants and the FDA for their guidance on PMTA requirements.