Redesigning an Existing Application

A Comprehensive Playbook

As business landscapes evolve and customer and end-user needs shift, company leaders are increasingly confronted with the complex task of redesigning existing applications. The stakes are high, and product design is key to success. Redesigning an application isn't just a business adjustment; it reflects the company's evolving direction, ethos, and vision for the future. Amidst the whirlwind of aspirations, constraints, and competition, leaders might wonder: Where do we begin?

More importantly, how can they ensure that redesign efforts meticulously account for the current processes, systems, workflows, end-user expectations, and other integral components?

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The FullStack Playbook

Redesigning any application is intricate, requiring more than just an aesthetic revamp. It's about ensuring that the new design aligns seamlessly with the existing infrastructure while also innovating for the future.

This playbook serves as a comprehensive guide, leading company leaders step-by-step through the process of redesigning an application. From understanding the legacy systems to the final rollout of the redesigned app, this is your essential roadmap for turning digital aspirations into tangible outcomes. Remember, while this playbook sets the stage, your company's specific goals and a deep comprehension of existing client processes are the driving forces behind your application's successful redesign.

Step 1

Kickoff & Discovery

In the foundation phase of app redesign, we build a deep understanding of legacy systems, processes, and tools. Here, we ensure that the redesign not only meets the client's new vision, but also integrates seamlessly with the established infrastructure.


Build a comprehensive understanding of the current application's setup, goals for the redesign, inherent challenges tied to legacy systems, and devise a strategic plan to transition from the existing framework to the envisioned transformation seamlessly.


Knowledge Transfer

We dedicate time to familiarizing ourselves with the existing data, legacy platform(s), prior research, and any other foundational material the client provides. It's essential for us to understand the terrain before embarking on the journey.

Stakeholder Interviews

Engaging one-on-one with key stakeholders provides in-depth insights into their aspirations, concerns, and the strategic intent behind the application. This qualitative input is invaluable in crafting an app that aligns with the company’s larger objectives.

Define Goals & Objectives

We’ll identify key technical performance indicators and business-centric metrics such as user acquisition, conversion, and revenue potential.

Existing System Audit

We test and analyze the existing platform to understand the ecosystem in which the redesign will take place.

Scope Definition & Validation

This phase involves setting clear boundaries and validating the proposed redesign against legacy processes. What features are essential for the MVP (Minimum Viable Product)? Which ones can be integrated from existing systems or scheduled for later phases? By defining and cross-referencing the scope with the legacy processes, we ensure that the redesign project remains not only focused and feasible but also aligned with established workflows.

Competitive Benchmarking

We analyze the market to identify direct and indirect competitors, assessing their strengths, vulnerabilities, and unique selling points to gain insights that position the application uniquely in the market landscape.

Key Deliverables

Evidence of our new knowledge and a clear path forward for the next phase.

Step 2

User Experience Design

As the core of user-centric design, this phase dives into the mind of the end-user, weaving a seamless journey that marries utility with delight.


We aim to craft an intuitive and engaging user experience (UX), merging client aspirations with actual user needs. It's not just about building an app, but ensuring users value, enjoy, and advocate for it.


Information Architecture

Think of this as the blueprint of a building. A logical, structured content framework ensures users don't get lost in the digital maze. We ensure that all features, carried over from the legacy platform, are accounted for.

User Flows

We trace the digital footprints of users, understanding every interaction, decision point, and transition. These flows also account for users transitioning from the legacy platform to the newly redesigned platform.


Wireframing allows us to create the general layout of the screen without having to decide on the exact text and imagery that will be used in the final designs. It's useful for:

  • Rapid Prototyping
  • Understanding Functionality
  • Demonstrating the User Flow
  • Ensuring a Solid Underlying Structure

Usability Testing

Here we take our prototype on a test drive with real users, seeking feedback and insights. By conducting this early on with low-fidelity prototypes, we are able to rapidly iteration on the proposed solution.


Digital inclusivity is our mantra. We ensure the design speaks to everyone, including those with disabilities. Our team follow WCAG AA guidelines and the designs are set up to reflect them.

UX Validation

We compare proposed UX design with the legacy design systems, ensuring the redesigned user experience does not compromise essential functions from the legacy systems.

Key Deliverables

Detailed documentation about the users and plans for how they will interact with the app.

Step 3

Technical Discovery

This stage is where design meets technology. We ensure that our app's blueprint aligns with a technology stack that's robust, scalable, and agile.


We will conduct a thorough assessment of your product requirements, UX designs, and UI designs to balance priorities and gauge the scope of development. This involves reviewing your needs and selecting the best-fit technology stack for seamless integration and future scalability.


Existing Technology Review

FullStack will review your current tech stack and list the languages, frameworks, and other significant existing and proposed dependencies of the project. Our engineers will then determine whether we need to update the existing app's dependencies to complete the project.

Tech Stack Research and Recommendations

Choosing the appropriate tools and the right combination of tools directly correlates to an app's performance, scalability, maintainability, and budget. 

Our team will review your design and plans, as well as your existing technology, and determine the tech stack that best fits your job. This review includes determining what components will work best and leveraging past project experience and best practices to determine which resources, languages, and libraries will create an optimal ecosystem.

Architecture Ideation

Software architecture refers to the overall structure of a software system and the design decisions made to achieve desired qualities such as performance, scalability, and maintainability. It defines a software system's components, modules, interfaces, and data and outlines how they interact.

In this stage, our team will develop a rough understanding of how your redesigned application will function technically. They will work closely with you to analyze user stories and capture your project needs. 

Building a strong architecture is crucial to ensuring a robust and scalable foundation that supports the design and prepares the app for future iterations.

Key Deliverables

Assurance that what we are redesigning is technically feasible.

Step 4

User Interface Design

We move from the skeletal frame of UX to the artistry of UI. Here, we breathe life into the wireframes, suffusing them with color, typography, and graphics, ensuring that the digital interface doesn’t just function but captivates.


Breathe life into our wireframes, transforming them into vibrant, interactive visuals that captivate users. Through a meticulous design process, we ensure the application's aesthetics not only delight but also amplify its functionality and user experience.


Style Concepts

Style concepts demonstrate different options for the look and feel of your application, including colors, fonts, etc. We generally create two or three style concepts for you to choose from, each with its own unique look and feel. Prior to creating the concepts we review your existing platform to determine whether any visual elements should be retained. We combine these findings with your current brand guidelines to create the style concepts.

UI Validation

We compare the proposed UI design vs. legacy systems to determine what existing elements are kept, updated, or replaced.

Hi-Fi Mockups

High Fidelity Mockups serve as a visual representation of how the app will look. It incorporates the structure of the Wireframes with the visuals of the Style Guide. The mockups also incorporate visual assets like photography, illustrations, and icons. These serve as an accurate depiction of how the app will look when it launches.

Design System

Construct a cohesive, scalable set of design principles and components. This process ensures consistency across the interactions and visuals of the product. It also increases the velocity of the development efforts.

Responsive Design

Pulling everything together, we craft designs that fluidly adapt to varying screen dimensions. Our designers will build out high-fidelity mockups at each target breakpoint and provide guidance to the developers to do between them.

Key Deliverables

Visually appealing mockups based on a solid foundation.

Step 5


Prototyping is our virtual sandbox. We simulate user journeys, validate our design hypotheses, and iterate. By enabling stakeholders and users to interact with a virtual version of the product, we refine, reassess, and revitalize our designs based on tangible feedback.


Craft dynamic prototypes to visually communicate the app's flow and functionality, giving stakeholders a tangible experience of the end product. This phase aids in refining design choices and ensures alignment between user needs, business goals, and technical constraints.  Prototypes are one key way product design helps developers work efficiently.


User Journey Prototypes

Create visual paths that showcase how users will navigate and interact within the app. This prototype will demonstrate how the user achieves their goal and may also explore edge cases.

Navigation Design

Develop a coherent and seamless flow, ensuring users find what they're looking for efficiently. In the prototype, users are able to navigate to all views of the app.

Interaction Design

Incorporate subtle animations and cues that enhance user engagement and provide feedback. These micro interactions create a seamless feeling to the app and build a sense of delight.

Error Handling

Demonstrate system responses, ensuring that users are guided gracefully through any hiccups.

A/B Testing

Compare design variations to pinpoint which version fosters better user engagement and conversion.

UAT Testing

Ensure the design meets requirements and offers a glitch-free experience in real-world conditions.

Stakeholder Acceptance

Collaboratively align the design with stakeholder expectations and business goals.

System Validation

We assess the new prototypes against existing legacy systems, ensuring advancements in usability and aesthetics while retaining essential features for the continuity and comfort of long-standing users.

Key Deliverables

Visually appealing mockups based on a solid foundation.

Step 6

Development Prep & Support

As the design crystallizes, we pave the way for its technical realization. This phase involves meticulously documenting our design, elucidating nuances, and ensuring the transition from design to development is seamless, devoid of misinterpretations or oversights.


Bridge the design and development phases seamlessly, ensuring every design detail is documented—paving the way for developers to translate the design into a functioning app without hitches.


Design Documentation

Create detailed notes capturing every design nuance, ensuring developers have a clear blueprint to follow.

Design Audit Of Development Releases

Continuously assess the app during development, ensuring the actual product aligns flawlessly with the intended design.

Demos for Developers

Develop in-depth video demonstrations that guide developers through the prototype, emphasizing intended behaviors and interactions.

Key Deliverables

Visually appealing mockups based on a solid foundation.

Step 7

Launch & Refinement

This is the moment we've been working towards: launching the app to the market. But our work doesn't stop there; after the launch, we listen to users, gather feedback, and make any necessary refinements to ensure your app remains top-tier.


Delivery of polished launch across channels, ensuring a stellar user reception. Post-launch, harness user feedback and analytics to fine-tune and elevate the application experience.


App Store Assets

Design and prepare compelling visual assets that accentuate the app's features, ensuring it stands out in app marketplaces.

Feedback Analysis

Dive deep into user reviews and feedback to pinpoint areas that can be enhanced, ensuring a user-centric evolution of the app.


Return to the design phase with fresh insights from real-world usage, tweaking and enhancing the app to meet evolving user needs and expectations.

Key Deliverables

Visually appealing mockups based on a solid foundation.

Redesign an Existing App with FullStack Labs

Redesigning an existing application is a nuanced undertaking that demands an astute approach, as it involves preserving the legacy while introducing innovation. At FullStack Labs, we excel in navigating this delicate balance. 

Transparent Collaboration

Recognizing that every redesign is rooted in history, we align with both your past and your envisioned future. Whether our clients seek immersion in every detail or prefer overarching insights, we commit to clarity and transparency throughout the journey.

Redesign Excellence with Legacy Respect

Redesigning is not merely about modernization—it's about creating a bridge between the familiar and the new. Our commitment is to high-fidelity designs that meld the legacy's strength with innovative UX, ensuring every touchpoint resonates with both familiarity and fresh appeal.

Need to re-think a current product or application? Contact our experts at FullStack Labs, and together, we'll guide every transformational step.

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