What is Tangerine Central?

Tangerine Central is a women-owned small business dedicated to advancing efficient, effective data collection and use in any setting, whether online or offline. Our mission is to ease the burden of data collection and deliver timely, actionable insights in even the most resource-constrained settings.    

Guided by the principles of Data Sovereignty and Security, Adaptability and Simplicity, and Community-Driven Development, we believe widely accessible, usable, and trustworthy tools are essential for communities to shape their own futures.  

Our team includes a global roster of experienced Tangerine users and developers who provide hands-on support with instrument design, deployment, and data analysis. We offer training and capacity building through online courses, helping partners build the skills needed to use Tangerine effectively and independently.  

Tangerine Central is here to help you collect meaningful data that drives learning and equity. 

Learn more about our co-founders. 

Tangerine Central brings together a global roster of seasoned professionals who specialize in using Tangerine to improve education data systems. Our network includes impact evaluation designers, instrument developers, assessor trainers, statisticians, and data visualization experts—many of whom helped pioneer the very tools and methods now widely used to assess early literacy and numeracy. 

These experts provide hands-on support to partners around the world, helping design reliable and valid instruments, deploy assessments in diverse contexts, and analyze data to inform policy and practice. Whether you're launching a national learning assessment, conducting a program evaluation, or building dashboards to visualize results, our team is ready to help. 

We don’t just support projects—we build capacity. Through training, mentorship, and peer collaboration, we help local organizations and governments take ownership of their data systems. Our community literally ‘wrote the book’ on early literacy and numeracy assessments, and we’re committed to sharing that knowledge to strengthen learning outcomes globally. 

Learn more about how the Tangerine software works. 

From Paper to Progress: The story of Tangerine 

Tangerine was born out of first-hand experience collecting student data in low-resource and remote contexts. During a particularly challenging early grade reading assessment conducted as part of an RTI International project, co-founders Carmen and Amber found themselves buried in paper forms, battling malfunctioning staplers, illegible print copies, and chasing missing data. The process was slow, outdated, and error prone. They knew there had to be a better way. 

That moment sparked the creation of Tangerine: a digital solution designed to improve data quality, streamline fieldwork, and enable real-time monitoring — no more waiting weeks to discover surprises in the data. What started in 2011 as a tool designed specifically for early reading assessments has grown into a versatile, offline-first platform used in over 65 countries for everything from tracking student attendance to survey research. 

In 2025, Tangerine was brought under the management of Tangerine Central, led by Carmen and Amber. With improved flexibility and a dedicated team, Tangerine Central will continue to leverage Tangerine to help even more governments and organizations unlock the power of data to improve lives.  

Our guiding belief?  

Quality, timely data has the power to change lives for the better, and is essential to helping communities shape their own futures. 

Get to Know our Leadership 

  • Carmen Strigel, Co-Founder & Chief Executive Officer

    Carmen Strigel is a lifelong advocate for data-driven decision-making and accessible education for all. With deep expertise in EdTech, large-scale assessments, and systems strengthening, she has led innovations that empower educators and learners worldwide. Carmen created the Tangerine platform to support offline-first data collection and real-time monitoring in low-resource settings. As CEO of Tangerine Central, she guides operations, strategy, and innovation—advancing open-source tools and locally led solutions that unlock the power of data for learning and transformation. Her leadership reflects a commitment to impact, inclusion, and building tools that are simple, scalable, and responsive to the needs of communities. 

    Carmen also serves as Senior Director, Center for Advanced Analytics and Visualization at RTI International. These dual roles help ensure alignment and momentum in advancing the two organizations’ shared goals around education, innovation, and improving the human condition. 

    Connect on LinkedIn

    Contact Carmen

  • Amber Gove, Co-Founder & Chief Impact Officer

    With over two decades of experience in education research, policy, and implementation across more than 20 countries, Amber brings deep expertise in applied research and the design of scalable, context-sensitive learning assessment and improvement approaches. She co-developed the globally recognized Early Grade Reading Assessment (EGRA) and the open-source Tangerine platform, key tools for advancing data-driven decision-making in low-resource settings. As Chief Impact Officer, Amber leads strategy to expand impact and reach, foster collaboration, and promote local ownership. Her work centers on translating evidence into action—brokering knowledge across sectors and supporting local partners to use high-quality data to improve education outcomes.   

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    Contact Amber

  • Lachezar Hristov, Head of Implementation

    Lachko is a seasoned technologist and product leader with over 15 years of experience in software development and implementation across education, health, and agriculture. As the driving force behind Tangerine’s technical evolution, he has led the design, deployment, and support of its ecosystem across more than 50 projects. Fluent in multiple languages and technologies, Lachko brings deep expertise in agile development, user-centered design, and scalable solutions for low-resource environments. As Head of Implementation, Lachko guides the design, configuration, testing, and rollout of the platform globally. He is deeply committed to working alongside local partners to co-create solutions that are contextually grounded and sustainably impactful. 

    Lachko also continues as a Senior Technical Advisor at RTI, supporting technology solutions in the Center for Advanced Analytics and Visualization. 

    Connect on LinkedIn

    Contact: Lachko