Is your contact list up to date?

Contacts411 is a productivity mobile app for individuals, salespeople, and small businesses to help them find, update & verify contacts. It gathers high-quality triple verified information on U.S. consumer and business contacts from over 13,000 verified, available data sources. DECODE makes sure that your contact list stays up-to-date and, most importantly, private.

new hero image c411

Short summary


Social Networking




2018 – 2023


Mobile app development
Web app development


Mobile – React Native
Backend – Node.js


Project manager
2 Software engineers
QA engineer

Contacts411 is a smart contacts data update application.

The challenge

Keeping contact data current is a daily challenge given how often people move and or change jobs. It is estimated that on average 10% of the US population moves every year and over 30% of individuals change jobs annually.

The solution

Contacts411 provides users with a simple system that uses extensive reference database assets. It integrates directly with iOS and updates both personal and business data efficiently and cost-effectively.

All the while keeping the users’ address books private.

Our teams were hired to develop new features, update and maintain the existing codebase, to implement a new UX/UI for the mobile app and to develop and maintain their web app.

c411 brand
c411 contacts management app

Our impact

New mobile features

Many new features were added to the app, the most notable being the complex ability to update business and contact info at the same time.

Back-end architecture

We migrated a part of the client’s backend system from Python 2.7. to JavaScript (Node.js). The goal was to make the system easily maintainable and integrate it with new features.

Full UX/UI redesign

After we’ve set everything up on the technical side, we’ve turned to the design. We’ve modernized the client’s mobile and web apps and made sure the design followed all of the latest guidelines.

Website & web app improvements

On top of our work on the existing mobile app, we helped create the client’s website and maintained their admin web app written in React.js.

Existing codebase maintenance

There was a hefty amount of existing code that had to be maintained and merged with all the new features.

They brought in the expertise in the area of mobile application architecture, automated deployment & testing, introducing new development paradigms and workflows.
Karen Sallick

Tech stack & tools

React Native

React Native

Used for mobile development and upgrading existing code.



We used it for backend to make the app easily maintainable.



Our UX/UI team created wireframes, and user interfaces using this tool.

Jira 1


Jira is a robust tool for project management, and after using it for a long time, we know it inside out.



Our go-to tool for server hosting, databases or handling third-party events.

c411 app
c411 app 2


The app is continuously improved with new features and updates to make it absolutely reliable and secure.

Seamlessly integrated with the iOS address book, with a single touch users can add new contact information to their address book or call, text, email, map the address, and merge duplicate contacts into one.

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