Prototyping of AI-Powered Menstrual Monitoring Technology

For Joii, an Irish femtech startup, we developed a functional prototype of the innovative period technology that improves menstrual well-being.

Joii - smiling woman using smartphone in her room

The company and product

Joii is a Dublin-based period care brand, dedicated to empowering every woman to experience their best menstrual wellbeing. It is the first technology to provide quantified menstrual health data through image analysis.

Joii was founded in 2019 by Justyna Strzeszynska, who was frustrated by the gap between how periods are experienced versus how healthcare professionals understand them. Joii was created to turn periods into measurable health data and 'make periods visible, measurable and taken seriously. It is a groundbreaking period tracking app that uses AI-powered computer vision technology to accurately measure menstrual flow volume and clot sizes by scanning photos of used period pads.

Scope and Highlights

UX/UI Design

Proof of Concept

Hybrid Flutter Development

Joii app for menstrual health screenshot

The Challenge

When Joii approached Monterail, they were at the “no one has done it before” stage and needed a technical partner to move forward.

The menstrual health startup needed to transform their innovative concept which was using AI to analyze period flow from photos into a functioning mobile application. The most challenging part was creating an accurate, real-time image analysis tool that could integrate with developed applications for both iOS and Android platforms.

Key challenges

Developing an app for iOS & Android platforms using Hybrid Flutter.

Creating a scanner prototype - an accurate, real-time image analysis tool.

Integrating the scanner prototype with the developed apps.

Developing an app for iOS & Android platforms using Hybrid Flutter.

Creating a scanner prototype - an accurate, real-time image analysis tool.

Integrating the scanner prototype with the developed apps.

The Process

The team built the solution around three main things: Joii's product needs, the medical side of menstrual health, and how real users would actually use the app.

Using Hybrid Flutter, we built applications for both iOS and Android so that Joii could reach users on any device. Then came the big task, creating the scanner that could actually analyze photos accurately. This scanner had to work in real conditions with different lighting and camera angles.

Next, we connected the scanner to the mobile apps so everything worked together smoothly. We also explored personalization options to ensure the maximum value for users.

Joii Application

The Outcome

The client received a functional prototype of the mobile app with the integrated scanner.

We improved user navigation in the app by adding better guidance features, making it easier for people to use the technology for the first time. The biggest win was achieving 99% accuracy in image processing, which effectively turned Joii's idea into a medically reliable solution.

The technology provides users with precise measurements of flow volume in milliliters, clot detection, and cycle trend analysis, addressing the lack of objective data in menstrual health monitoring. Users of the app can now have credible, data-backed conversations with their doctors instead of relying on subjective descriptions.

We successfully connected the scanner with both the iOS and Android apps, so Joii could launch knowing users would get the same accurate experience on any phone.

The app was further developed and launched in 2025–it is now available for free on iOS and Android platforms. The technology holds Class I Medical Device certification in the UK and is protected by multiple patents.

Partnership results

Improved user experience through implementing user guidance.

Enhanced current image processing resulting in 99% scanner accuracy.

Successful integration of the scanner prototype with iOS and Android apps.