Running customer support over WhatsApp with no way to assign conversations to agents, track resolution times, or see what was promised?
Managing a community of thousands in a consumer chat app that has no member management, moderation tools, or analytics?
How to Build an App Like WhatsApp
WhatsApp handles 100 billion messages per day. Most businesses using it for customer support, team communication, or community management are doing so on a consumer platform not designed for business workflows. A custom messaging platform gives you control over data, user experience, and monetisation.
This guide is for founders building a niche community platform, a business communication tool, or a customer-facing messaging product -- not developers.
Real-time messaging with delivery and read receipts across mobile and web
Business inbox with agent assignment, conversation history, and resolution tracking
Group channels and community spaces with moderation and member management
Secure file, image, and document sharing with access controls
Building a messaging app like WhatsApp for business use costs $60,000--$150,000 depending on features. Core modules include real-time messaging, push notifications, group channels, file sharing, and business inbox management. A minimum viable platform ships in 14--20 weeks. RaftLabs builds messaging platforms at fixed cost.
100+Products shipped
·24+Industries served
·FixedCost delivery
·12-14Week delivery cycles
Why building a messaging platform makes business sense
WhatsApp built its user base on simplicity. But simplicity for consumers creates problems for businesses. There is no agent routing. There is no conversation history linked to a CRM. There is no way to enforce compliance on what your team says to customers. There are no analytics.
Businesses in healthcare, financial services, legal, and enterprise sales increasingly need messaging that operates under their own data policies. Consumer apps store data on servers outside your jurisdiction and do not offer the audit trails that regulated industries require.
If you run a B2B SaaS product, a professional community, a marketplace, or an enterprise communication tool, owning your messaging layer means owning the most engaged part of your user experience. It also means choosing your own monetisation model instead of being subject to Meta's platform decisions.
What makes WhatsApp work
WhatsApp works because it is fast, reliable, and available on every device. The core technical achievement is a persistent connection that delivers messages in under a second even on poor mobile connections. End-to-end encryption builds the trust that makes users share sensitive information.
For business use, the features that matter most are the ones WhatsApp does not have: conversation assignment, resolution tracking, message templates for compliance, broadcast management with opt-in controls, and agent performance reporting. A custom platform can have all of these built in from day one.
Core features you need to build
Real-time messaging infrastructure
A WebSocket-based messaging layer that delivers messages in under a second and maintains connection state across mobile and web clients simultaneously. Messages display delivery status (sent, delivered, read) in real time without requiring the recipient to refresh their screen.
Message queuing handles offline recipients -- messages are stored and delivered the moment the user reconnects. Typing indicators show when the other party is composing a reply.
The infrastructure must support concurrent sessions across multiple devices for the same user. This is the technical foundation that separates a real-time chat product from an email-style messaging system.
Push notifications
Push notifications deliver new message alerts to iOS and Android devices even when the app is closed. Notification payloads carry enough context -- sender name, message preview, conversation thread -- that users can decide whether to open the app or wait.
Notification preferences let users mute individual conversations, set quiet hours, or disable alerts for low-priority channels without turning off all notifications. Badge counts on the app icon show total unread messages at a glance.
For business messaging platforms, push notifications are a direct engagement channel. Configuring them properly -- so they inform without annoying -- is one of the decisions that determines whether users adopt the platform daily.
Group channels and communities
Group chats support many-to-many conversations with configurable member limits, admin roles, and moderation tools. Admins can restrict who can send messages, pin announcements, remove members, and control who can add new participants.
Community spaces organise multiple related groups under a single hub. A fitness platform might have a community for each training cohort, with sub-groups for each week's workout, nutrition questions, and coach announcements.
Broadcast channels allow one-to-many communication where members can react but not reply directly. This is the pattern used by media brands, creator communities, and enterprise announcement boards that need controlled distribution without group noise.
Business inbox and agent routing
A shared inbox where all incoming customer conversations are visible to a team and can be assigned to specific agents. Assignment rules can route conversations automatically based on topic, customer tier, language, or agent availability.
Each conversation carries a full history including previous agent interactions, any CRM notes pulled from your customer database, and all attachments sent. Agents see context before they type a single word.
Resolution tracking shows open time, first response time, and close time for every conversation. Supervisors see agent workload and queue depth in real time. This is the business inbox layer that transforms WhatsApp-style chat into a customer service operation.
Media and file sharing
Image, video, audio, and document sharing with file size limits configurable by plan or user role. Preview rendering for images and videos lets recipients see content without downloading. Document sharing supports PDF, spreadsheet, and presentation formats with in-app viewing.
Access controls determine who can share files in which channels. Regulated industries need the ability to disable file sharing in certain conversation types or require approval before files are sent to external parties.
Storage management tools let admins set retention policies -- automatically deleting media after a defined period or archiving to cold storage -- to control infrastructure costs as the platform scales.
Message search and history
Full-text search across all conversations, returning results scoped to the searching user's access permissions. Search results show the message in context with a link to open the conversation at that point.
Conversation history is stored and retrievable for compliance, dispute resolution, and institutional knowledge. For regulated industries, export tools produce conversation logs in formats acceptable to compliance auditors.
Archiving moves old or resolved conversations out of the active inbox without deleting them. Pinned messages surface key information -- a meeting link, a shared document, an important decision -- at the top of the relevant conversation so it does not get buried.
Business model options
A business messaging platform can monetise in several ways. Per-seat SaaS subscription is the most common -- charging per active user per month with tiers based on features like admin controls, compliance tools, or API access.
Per-message API fees apply when you expose messaging as a service to other businesses. You charge a fraction of a cent per message sent through your platform, similar to how Twilio and MessageBird price their APIs. This model scales with usage rather than headcount.
Enterprise licensing offers a single annual fee for large organisations that want to deploy the platform within their own infrastructure. White-label and OEM deals let you sell the platform to other software companies that embed your messaging layer in their products.
What RaftLabs builds for you
Real-time messaging backend
We design and build the WebSocket server, message queue, and delivery infrastructure that handles concurrent connections at scale. Architecture decisions at this stage -- connection pooling, message persistence strategy, media storage -- determine whether your platform costs $500 per month or $5,000 per month to run as you grow.
You get a fixed scope and fixed price before any contract is signed.
Web and mobile apps
Browser-based web app and native iOS and Android mobile apps built on a shared React Native codebase. Users get a consistent experience across devices. The web app works in any modern browser without requiring a download.
Admin panel for managing users, channels, and settings. Role-based access controls built in from the start.
Business inbox and routing
Shared inbox for customer-facing teams with conversation assignment, agent notes, and resolution tracking. Integration with your existing CRM or customer database so agents see account context inside the inbox.
Configurable routing rules that assign conversations automatically based on your team structure. Supervisor dashboard with live queue metrics.
Compliance and data controls
Message retention policies, audit log export, and data residency configuration for regulated industries. Configurable encryption at rest and in transit. Content moderation tools including keyword filters and manual review queues.
These controls are designed for healthcare, finance, and legal platforms that need messaging but cannot use consumer apps for compliance reasons.
Launch and ongoing support
Production deployment on your preferred cloud infrastructure. Load testing before launch to confirm your platform handles the user volume you expect. Staff training and onboarding documentation for your team.
Post-launch bug fixes included. Monthly maintenance retainer available for feature additions after go-live.
Frequently asked questions
A core business messaging platform with real-time messaging, push notifications, group channels, file sharing, and a business inbox typically costs $60,000--$100,000. Adding compliance controls, CRM integration, agent routing, and audit log tools typically brings the total to $90,000--$150,000.
Cost depends on the number of concurrent users, mobile platform requirements, compliance features, and whether you need API access for third-party integrations. We scope every project before pricing.
A minimum viable messaging platform with real-time chat, push notifications, groups, and file sharing ships in 14--18 weeks. A full platform with business inbox, agent routing, compliance tools, and admin dashboard takes 18--24 weeks.
We deliver in phases so you can launch a working product and iterate based on real user behaviour before the full feature set is complete.
The architecture decisions we make during scoping -- WebSocket connection pooling, message queue design, media storage strategy, database sharding -- are the primary levers that determine how your platform performs at 1,000 users versus 100,000 users.
We build for your expected scale from day one and document the upgrade path for the next order of magnitude. Platforms we build typically handle 10,000 concurrent connections without infrastructure changes.
Yes. End-to-end encryption means messages are encrypted on the sender's device and can only be decrypted by the recipient -- the server never sees plaintext content. The trade-off is that server-side features like search, moderation, and compliance archiving cannot inspect message content.
Most business messaging platforms use transport encryption (TLS) rather than end-to-end encryption for this reason. We will recommend the right approach based on your compliance requirements and feature needs.
Yes. We build web apps (browser-based), iOS apps, and Android apps. Messages sync across all devices in real time -- a conversation started on mobile continues on desktop without any manual sync step.
We use React Native for mobile apps so that a single codebase covers both iOS and Android. This reduces ongoing maintenance cost compared to maintaining two separate native codebases.
