Giving Global Learners a Better Way to Learn, Practice, and Speak a New Language — with AI
Quick Snapshot
You can memorize hundreds of words and still freeze when someone speaks to you. Language confidence comes from using those words in real conversations—hearing different voices, responding in the moment, making mistakes, and trying again.
YooSpeak solves this by bringing learning, live practice, and AI conversation together with VE building the mobile app and web platform.
Language Learning, Looked at Differently
The Client
Teacher Yoos LLC (USA) is an online language education company founded by Youssel Calisme, a Certified ESL Teacher and professional Medical & Legal Interpreter. The company helps adults, including immigrants and ESL learners, build practical English skills for work, healthcare, business, and everyday communication.
What Was Needed
Youssel Calisme envisioned YooSpeak as a live language-learning ecosystem where learners could move beyond passive lessons and build confidence through real interaction. The platform would also give teachers a global marketplace for finding students, delivering classes, selling courses, managing schedules, and earning through their expertise.
How VE Fit In
The initial ask was to build an MVP. As the product took shape, the scope grew into a full language-learning platform with mobile, web, admin, real-time communication, AI, payments, and media capabilities. VE handled that journey end to end, from development and integration through testing, deployment, and continued improvements.
The Closer Learning Gets to Real Life,
the More There Is to Get Right
The Project
If learning a language is ultimately about being able to use it confidently, then lessons alone are not enough. YooSpeak was planned as a language-learning platform where learning continues through real interaction - with teachers, other learners, and AI. A learner can take a lesson, practice with another person, join a conversation, or use AI to practice independently. Teachers have their own side of the experience, where they can teach, create courses, manage students, and earn from their expertise. This makes YooSpeak more than a place to consume lessons. It is being designed around what happens before, during, and after the lesson, giving learners more opportunities to actually use the language they are learning.
The Challenge
The best version of YooSpeak would make a complicated system feel almost invisible.
A learner should see a class time, not a timezone conversion. A teacher should see earnings, not a chain of financial transactions. A user should join a video call, not think about signaling or network recovery. An administrator should see a verified teacher, not the checks behind that decision.
The challenge was hiding this complexity without simplifying the rules that made the platform work. Every important interaction had to remain accurate, secure, and predictable underneath.
The Solution
Meet YooSpeak —
Turning Language Learning into Active Practice With AI
Once learning becomes a live service between strangers, trust becomes part of the product. Who is allowed to teach? Can a learner safely pay for a class? Does the teacher get the right amount? What happens when a class is cancelled, a payment is retried, or a connection drops?
VE built YooSpeak around these realities, connecting teacher verification, scheduling, live communication, payments, subscriptions, coins, refunds, and payouts into the product itself. Real-time services handle classes and conversations, while AI adds another way to practice. Behind the experience, the web platform, mobile app, backend, and admin system work together to manage the rules, transactions, and interactions that users simply experience as learning.
Technical Build
Live Classes
Learners can join one-to-one lessons or group classes, while teachers create slots, manage sessions, track attendance, and support structured online learning.
Language Practice
Learners can find practice partners, join role-based conversations, communicate through live sessions, and practice language skills with real people beyond scheduled classes.
Learning Content
The app supports courses, lessons, quizzes, workbooks, homework, vocabulary content, daily conversation clips, and teacher-created videos for structured learning.
Community
Learners can participate in language communities, share posts, watch video feeds, comment on content, and connect with people practicing similar languages.
Teacher Discovery
Learners can discover teachers, review available learning opportunities, select classes, and build their learning journey around their preferred language and schedule.
Practice Partners
The platform supports one-to-one matching between learners for real conversation practice, allowing users to improve through spontaneous interaction with other people.
AI Practice
Learners can practice conversations with an AI tutor, receive responses instantly, and use AI as an additional way to build speaking confidence.
Cross-Platform App
Flutter provides one shared application codebase for Android and iOS, maintaining consistent interfaces and functionality while supporting platform-specific mobile behavior.
Live Video
ZEGOCLOUD supports real-time voice, video, chat, and live streaming, enabling private practice sessions as well as larger online classroom experiences.
Call Signaling
Socket.io manages call invitations, active presence, ringing states, notifications, and connection events alongside Agora and Zego real-time media services.
Real-Time Chat
WebSocket-based communication supports instant messaging and live status updates, keeping conversations synchronized while users communicate across different network conditions.
Network Reliability
Real-time interactions include error handling and recovery mechanisms designed to maintain communication when connections change, sessions close unexpectedly, or networks become unstable.
AI Conversations
Gemini API powers AI-based conversation practice, giving learners an interactive alternative to teacher-led sessions and helping them practise communication whenever they choose.
Push Notifications
Firebase Cloud Messaging delivers notifications for classes, messages, updates, reminders, and other important activities across Android and iOS devices.
Scheduled Alerts
Backend scheduling handles time-sensitive notifications, including class reminders and other automated updates, using node-cron and node-schedule background processes.
Live Updates
Real-time services keep users informed about communication events, active sessions, messages, and changing platform states without requiring repeated manual refreshes.
Virtual Coins
The platform uses an internal coin economy for premium classes, content, and practice sessions, connecting purchases with bookings, deductions, earnings, and refunds.
Subscriptions
Tiered membership subscriptions support recurring access to premium functionality, with backend logic maintaining user entitlements and subscription-related platform states.
Secure Payments
PayPal supports online payment processing, while backend validation and secure API communication help protect transactions and sensitive financial information.
Teacher Verification
Multi-step verification supports government ID checks, blue-badge verification, questionnaires, and bank-detail validation before teachers can participate fully in the marketplace.
Flutter & Dart
Flutter and Dart power the Android and iOS applications from a shared codebase, providing consistent interfaces, native compilation, and efficient cross-platform development.
MVVM & Provider
MVVM separates presentation, business logic, and data layers, while Provider manages application state efficiently and keeps the code modular and maintainable.
Dio & Retrofit
Dio and Retrofit provide efficient, structured REST API communication between the mobile application and backend, supporting consistent data exchange across core features.
Git & Figma
Git supports source control and collaborative development, while Figma supports interface design collaboration and implementation across the mobile product experience.
Learner Platform
The web experience gives learners access to courses, lessons, teachers, practice opportunities, community content, messaging, and other learning activities through responsive interfaces.
Teacher Platform
Teachers can manage courses, classes, students, schedules, communications, earnings, and other teaching activities through the web experience.
Course Management
Structured learning content supports lessons, quizzes, workbooks, homework, video tutorials, course materials, and downloadable learning resources.
Community Experience
Users can create posts, interact with content, watch video feeds, comment, and participate in language communities through the responsive web platform.
Class Scheduling
The system converts schedules across user time zones, using timezone information and UTC normalization to display accurate class times for learners and teachers.
Teacher Operations
Teachers can create class slots, manage students, communicate with learners, deliver sessions, and participate in the platform's earning and payout workflows.
Practice Connections
Learners can connect with practice partners and participate in real conversations, extending language learning beyond structured lessons and teacher-led classes.
Responsive Web
React, Redux Toolkit, SASS, Bootstrap, and responsive components support consistent web experiences across learners, teachers, and different screen sizes.
Admin Dashboard
The React-based Yousell-admin portal provides centralized control over users, teachers, transactions, verification workflows, refunds, audit information, and platform operations.
Identity Verification
Administrators can review government identification, teacher screening information, blue-check verification, and bank details before approving relevant teacher accounts.
Financial Oversight
Administrative workflows provide visibility into coin transactions, subscription activity, refunds, payouts, and financial records connecting learner payments with teacher earnings.
Access Control
JWT, Passport, and role-based authorization protect administrative functions, while permission middleware controls access to sensitive operational and management capabilities.
Large Video Uploads
The platform supports course and homework videos up to 2GB, using extended upload limits, controlled processing, and backend handling for large media files.
Video Processing
FFmpeg handles compression, thumbnail extraction, media validation, and transcoding before files are stored in AWS S3 for reliable cloud-based access.
Document Generation
PDFKit and Puppeteer automate certificates, invoice receipts, downloadable reports, and other generated documents required across learning and administrative workflows.
Background Jobs
Node-cron and node-schedule automate temporary-file cleanup, scheduled notifications, maintenance tasks, and other background processes without requiring manual intervention.
Stripe Payments
Stripe handles payment intents, subscriptions, secure card processing, and webhooks, connecting financial transactions with the platform's internal coin and earning workflows.
Coin Ledger
The backend maintains consistency between real-money payments and virtual coins, covering purchases, class bookings, deductions, teacher earnings, and refund processing.
Secure Authentication
JWT provides token-based authorization, Bcrypt protects passwords, and Google OAuth supports social sign-in while HTTPS secures communication between applications and services.
Transaction Protection
Stripe webhook signatures, validation, retries, and controlled transaction handling help prevent spoofed requests, duplicate credits, and inconsistent financial records.
React & Redux
React 18 powers responsive web interfaces, while Redux and Redux Toolkit manage shared application state across learner, teacher, and administrative workflows.
Node.js & Express
Node.js 18+ and Express provide asynchronous REST APIs and backend services capable of supporting concurrent requests, WebSockets, payments, and real-time platform activity.
MongoDB & Mongoose
MongoDB stores flexible learning objects, users, courses, transactions, schedules, and other platform data, while Mongoose provides structured models and schema management.
AWS & Deployment
AWS S3 stores media and documents, while AWS EC2 hosts backend services managed through PM2, supporting production processes, automatic restarts, and reliable deployment.
And The People Started Using It, Globally
5,000+ Downloads
The YooSpeak app reached 5,000+ downloads within its first month, showing early traction among language learners.
Live Learning + AI
Learners can now move beyond traditional lessons through live classes, real-person practice, and AI-powered conversation, all within the YooSpeak experience.
4.6 App Rating
The app achieved a 4.6 rating, reflecting a strong early response from users across its mobile experience.
The Client Response
Says It All
“I would recommend VE to everyone. I don't know about any other clients, but me, I'm in love with VE.”
Founder, Teacher Yoos LLC, USA
