:: Case study / Secure communications

Encrypted chat and video, kept on the client’s own cloud

A US IT firm needed messaging, voice, video and group calls with end-to-end encryption, and every message stored on their private cloud rather than a third party’s.

Client: US IT firm

iOS, Android and desktop

End-to-end encrypted

Secure chat app showing an encrypted group chat on a phone next to a desktop group video call

The brief

A US-based IT firm needed a custom communication app that did more than send messages: text, voice calls, video calls, group video conferencing and group chats, with everything stored securely on its own private cloud.

Security was the foundation. Communications were often sensitive, so everything had to be protected by end-to-end encryption, from simple messages to group video calls. The app also had to be easy to use and handle high traffic across every mode of communication without losing performance.

:: The challenges

What made it hard

01

Encryption everywhere

End-to-end encryption on texts, voice, video and group calls.

02

Real-time quality

Group and video calls without lag or dropouts.

03

Scale

A growing user base and heavy traffic without slowing down.

04

Private cloud

Integration with the client’s own infrastructure for storage and access.

05

Every device

A consistent experience on mobile and desktop.

06

Easy to use

Calls, groups and file sharing that anyone can navigate.

Architecture of the secure communication app: iOS, Android and desktop clients with end-to-end encryption, connected to messaging, calling and file services on the client's private cloud

How the platform fits together

Users run the app on iOS, Android or desktop. Messages, calls and files are encrypted on the sender’s device and only decrypted by the intended recipients. Messaging, calling and group services run on the client’s private cloud, and all stored data stays there, so the client keeps full ownership and control. The services were built to scale out as users and traffic grow.

:: What we built

Everything in the app

Private cloud integration

All text, voice and video data stored in the client’s own controlled environment.

Real-time messaging

One-to-one and group chats with read receipts and typing indicators.

Voice and video calls

Switch between voice and video mid-call, tuned for low-bandwidth networks.

Group video conferencing

Several participants on one call with clear audio and HD video.

Group chats with file sharing

For casual conversations and work meetings alike.

Cross-platform apps

The same features and performance on mobile and desktop.

Scalable architecture

Ready for more users and more traffic over time.

End-to-end encryption

Only intended users can read messages or join calls.

A team meeting end to end: a message in a group chat, a file shared, a voice call upgraded to video, a group video conference, all encrypted and stored on the private cloud
Desktop app with a group video conference and participants list next to the mobile chat with read receipts

:: Delivery

How we delivered it

Platforms

iOS, Android and desktop

Services

UI/UX, mobile apps, dedicated developers

Data

Stored on the client’s private cloud

Security

End-to-end encryption

:: The result

What the client got

Communication

Real-time chat, calls and conferencing in one app

Control

All data on infrastructure they own

Reach

Consistent on mobile and desktop

Future

An architecture ready to grow

:: In the client’s words

“Sterling Technolabs delivered exactly what we needed: a secure and user-friendly communication app that fits our infrastructure perfectly. Their team was highly responsive and showed excellent technical expertise throughout the project.”

“Sterling Technolabs delivered exactly what we needed: a secure and user-friendly communication app that fits our infrastructure perfectly. Their team was highly responsive and showed excellent technical expertise throughout the project.”

MJ

Mike Johnson

Operations Manager, US IT firm

Watercolour meadow landscape

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