Published 27 January 2026 | Updated 29 October 2026
Technology
Cost to Build an App Like Arattai in 2026
What Is Arattai?
Arattai (Tamil for "chit-chat") is an instant messaging app from Zoho Corporation. It was soft-launched in January 2021 and offers one-to-one and group chats, voice and video calls, channels, stories, file sharing and meeting features. It works on Android, iOS, desktop and Android TV.
Quick answer
Building a messaging app like Arattai in 2026 costs about ₹25–50 lakh ($30,000–$60,000) for an MVP with one-to-one and group chat, media sharing and push notifications; ₹50 lakh–₹1.25 crore ($60,000–$150,000) for a full-featured app with voice and video calls, end-to-end encryption and channels; and ₹1.25–3 crore+ ($150,000–$360,000+) for an Arattai-scale platform built for millions of users, regional languages and desktop and TV apps. Monthly infrastructure costs range from about ₹50,000 for an early-stage app to several lakh rupees as usage grows. Arattai, built by Zoho, showed how fast an Indian messaging app can grow: daily sign-ups jumped from around 3,000 to more than 350,000 within three days in September 2025, and the app went on to pass 10 million downloads. This guide breaks down what it takes to build a similar app, feature by feature, with a realistic budget, tech stack and timeline.
- MVP ₹25–50 lakh, full-featured app ₹50 lakh–₹1.25 crore, Arattai-scale platform ₹1.25–3 crore+.
- Voice and video calling, end-to-end encryption and scaling to millions of concurrent users are the biggest cost drivers.
- Arattai stands out for privacy (no ads, data stored in India), support for low-end phones and slow networks, and multi-device use.
- Use proven protocols such as the Signal Protocol for encryption and WebRTC for calls rather than building them from scratch.
- Plan for running costs, moderation, compliance with India's DPDP Act and IT Rules, and spikes in sign-ups.
Why Arattai Grew So Fast in 2025
Lesson for founders: a messaging app can grow by millions of users in days. Your architecture has to be ready to scale before the spike, not after.
A push for Indian-made apps
In September 2025, calls to use homegrown digital products, including from government ministers, drove a surge of interest. Zoho reported daily sign-ups rising about 100x, from around 3,000 to more than 350,000 in three days, and the app topped app store charts in India.
Privacy positioning
Zoho states that Arattai shows no ads, does not monetise user data and stores data in India.
Built for Indian conditions
The app is designed to work on low-end phones and slow 2G and 3G networks, supports regional languages and allows large file transfers.
Encryption roll-out
End-to-end encryption came to one-to-one chats in late 2025, with group chat encryption following in 2026 updates, closing one of the main gaps compared with WhatsApp and Signal.
Cost to Build an App Like Arattai at a Glance
| Tier | What you get | Cost (INR) | Cost (USD) | Timeline |
|---|---|---|---|---|
| MVP | Android and iOS apps, phone OTP sign-up, one-to-one and group chat, media sharing, push notifications, basic admin | ₹25–50 lakh | $30,000–$60,000 | 3–5 months |
| Full-featured app | MVP plus voice and video calls, end-to-end encryption, channels, stories, multi-device sync, desktop app, moderation tools | ₹50 lakh–₹1.25 crore | $60,000–$150,000 | 5–9 months |
| Arattai-scale platform | Full app plus group calls and meetings, TV and web apps, regional languages, low-bandwidth mode, infrastructure for millions of concurrent users, security audits | ₹1.25–3 crore+ | $150,000–$360,000+ | 9–18 months |
Estimates assume an India-based team in 2026. A US or Western Europe team typically costs 2–3x more for the same scope.
Cost by Platform
| Platform | Approach | Approximate share of build cost |
|---|---|---|
| Android and iOS | Native (Kotlin and Swift) for best call quality, or Flutter or React Native for faster delivery | 45–55% |
| Backend and real-time messaging | Messaging servers, presence, delivery receipts, media pipeline | 25–35% |
| Web and desktop apps | Web app plus Electron or native desktop clients | 8–15% |
| Admin panel and moderation | User management, reports, analytics | 5–10% |
Features of an App Like Arattai and What They Cost
| Feature | What it includes | Approximate cost (INR) |
|---|---|---|
| Sign-up and profiles | Phone OTP, profile, contact sync, privacy settings | ₹1.5–3 lakh |
| One-to-one and group chat | Real-time delivery, read receipts, typing indicators, replies, reactions | ₹6–12 lakh |
| Media and file sharing | Photos, videos, voice notes, documents, compression, large file uploads | ₹3–7 lakh |
| Voice and video calls | One-to-one and group calls, network adaptation, call history | ₹8–20 lakh |
| End-to-end encryption | Signal Protocol for chats, key management, safety numbers, encrypted backups | ₹6–15 lakh |
| Channels and stories | Broadcast channels, followers, 24-hour stories | ₹3–8 lakh |
| Multi-device and desktop sync | Linked devices, desktop and web apps, message sync | ₹5–12 lakh |
| Meetings | Scheduled meetings, screen sharing, links for guests | ₹5–12 lakh |
| Regional language support | Localised UI, Indic keyboards and transliteration support | ₹2–5 lakh |
| Low-bandwidth mode | Data saver, adaptive media quality, offline queues | ₹2–6 lakh |
| Notifications | Push notifications via FCM and APNs, mute and priority controls | ₹1–2 lakh |
| Admin, moderation and reporting | Spam detection, user reports, content takedown workflows, analytics | ₹3–8 lakh |
Recommended Tech Stack
| Layer | Options |
|---|---|
| Mobile apps | Kotlin (Android) and Swift (iOS), or Flutter or React Native |
| Desktop and web | React web app; Electron, Tauri or native desktop clients |
| Real-time messaging | Erlang or Elixir (XMPP or custom protocol), Go, or Node.js with WebSockets |
| Calls | WebRTC with TURN and STUN servers, SFU media servers such as mediasoup, Janus or LiveKit |
| Encryption | Signal Protocol (libsignal) for end-to-end encryption, TLS for transport |
| Databases | Cassandra or ScyllaDB for messages, PostgreSQL for accounts, Redis for presence and caching |
| Messaging queue | Kafka or RabbitMQ |
| Media storage | S3-compatible object storage with CDN, hosted in Indian cloud regions |
| Notifications | Firebase Cloud Messaging and Apple Push Notification service |
| Infrastructure | Kubernetes on AWS, Google Cloud, Azure or Indian data centres, with auto-scaling |
What Makes Messaging Apps Expensive?
Real-time scale
Delivering messages instantly to millions of connected devices needs efficient connection handling, sharding and load testing.
Call quality
Calls must adapt to poor networks, which needs media servers, TURN relays and a lot of device testing.
Encryption done right
Getting key exchange, multi-device keys and backups right is hard, so use well-tested libraries and get an independent security review.
Device and network coverage
Supporting budget Android phones and 2G or 3G connections means extra optimisation and testing across many devices.
Sudden growth
A spike like Arattai's in 2025 needs auto-scaling, OTP capacity with SMS providers and support staff ready to respond.
Monthly Running Costs
| Cost item | Early stage (up to 50,000 users) | Growth (1 million+ users) |
|---|---|---|
| Cloud servers and databases | ₹30,000–₹80,000 | ₹5–20 lakh+ |
| Media storage and CDN | ₹5,000–₹20,000 | ₹2–10 lakh+ |
| TURN and media servers for calls | ₹10,000–₹30,000 | ₹2–8 lakh+ |
| SMS OTP | ₹5,000–₹25,000 | ₹2–10 lakh+ (depends on sign-ups) |
| Monitoring, security and moderation tools | ₹5,000–₹20,000 | ₹50,000–₹3 lakh |
| Maintenance and updates team | ₹1.5–4 lakh | ₹10–30 lakh+ |
Costs rise mainly with media volume and call minutes, not with the number of text messages. Compression, storage limits and peer-to-peer calls where possible keep bills down.
How We Build a Messaging App Like Arattai
Discovery and scope
We define your audience, unique angle, must-have features and compliance needs, and produce a fixed estimate.
UX and UI design
We design simple, familiar chat flows, with layouts that work for regional languages and small screens.
Architecture and MVP build
We build the messaging core, sign-up, media and notifications, with scaling and encryption planned from the start.
Calls, encryption and advanced features
We add WebRTC calls, Signal Protocol encryption, channels, stories and multi-device sync.
Testing and security review
We run load tests for sudden spikes, test on budget devices and slow networks, and arrange an independent security audit.
Launch and scale
We release on Google Play and the App Store, monitor performance and scale infrastructure as users grow.
Compliance and Trust in India
Digital Personal Data Protection Act, 2023 (DPDP Act) and DPDP Rules
Consent notices, purpose limitation, data principal rights and breach reporting.
IT Rules, 2021
Messaging services with large user bases have extra obligations, such as grievance officers and, for significant social media intermediaries, traceability requirements that are under legal challenge. Get legal advice early.
Data localisation
Hosting in India is not mandatory for every app but builds trust, as Arattai has shown.
App store policies
User-generated content apps need reporting, blocking and moderation tools.
How Can a Messaging App Make Money?
Arattai is ad-free and backed by Zoho's wider business. A new messaging app needs a clear revenue model:
Business messaging
Paid APIs or verified business accounts for customer communication.
Premium plans
Extra storage, larger file limits, custom themes or advanced meeting features.
Enterprise and team editions
Secure internal messaging for companies and government.
Payments and commerce
In-chat payments or mini-apps, subject to RBI and NPCI rules.
Paid channels and creator subscriptions
Revenue sharing with creators.
Frequently Asked Questions
Quick answers related to this article from PerfectionGeeks.
1. How much does it cost to build an app like Arattai?
2. How much does it cost in US dollars?
3. How long does it take to build a messaging app like Arattai?
4. Who owns Arattai?
5. Is Arattai end-to-end encrypted?
6. Why did Arattai become popular?
7. Can I build an Arattai clone cheaply?
8. Which is cheaper: native or cross-platform?
9. What is the most expensive feature of a messaging app?
10. How much does it cost to run a chat app every month?
11. Does a chat app in India need to follow the DPDP Act?
12. How can a new messaging app compete with WhatsApp?
Conclusion
Tell us your audience, must-have features and launch markets. We will send a feature-by-feature estimate in INR or USD, a timeline and a scaling plan.Get a Fixed Estimate for Your Messaging App
Shrey Bhardwaj is the Director & Founder of PerfectionGeeks Technologies, bringing extensive experience in software development and digital innovation. His expertise spans mobile app development, custom software solutions, UI/UX design, and emerging technologies such as Artificial Intelligence and Blockchain. Known for delivering scalable, secure, and high-performance digital products, Shrey helps startups and enterprises achieve sustainable growth. His strategic leadership and client-centric approach empower businesses to streamline operations, enhance user experience, and maximize long-term ROI through technology-driven solutions.