en flag +1 214 306 68 37

Payment App Development: A Step-By-Step Guide

How to Build a Successful Solution

ScienceSoft applies 19 years of experience in payment software development to help companies design and build robust payment applications.

How to Build a Payment App - ScienceSoft
How to Build a Payment App - ScienceSoft


Darya Ilyushina

ScienceSoft's Web and Mobile Development Manager

Natallia Babrovich

ScienceSoft's Financial and Banking IT Consultant

Payment Application Development: Summary

Payment app development helps companies provide their customers with a fast and convenient way of sending and receiving digital payments. Custom payment apps offer comprehensive functionality for funds management, support all required payment methods and currencies, provide advanced security of customer’s personal and payment data, and can be easily evolved with new features.

Key steps to create a payment app

  1. Analyze payment needs and create requirements.
  2. Plan the project's scope of work, duration, and budget.
  3. Design the payment application.
  4. Select the appropriate tech stack.
  5. Develop the payment app.
  6. Integrate the application with the necessary systems.
  7. Conduct quality assurance.
  8. Deploy the payment application.
  9. Provide support and evolution for the solution.

Timelines: 6–11 months on average.

Cost: $150,000–$2,000,000+, depending on the type of a payment app. Use our free calculator to estimate the cost for your custom solution.

Team: a project manager, a business analyst, a solution architect, a UX designer, a UI designer, a front-end developer, a back-end developer, a DevOps engineer, a QA engineer.

ScienceSoft can provide all necessary competencies to help companies roll out reliable, secure, and visually appealing payment applications that ensure seamless payment experience for their target audience and drive high ROI.

Types of Payment Applications We Develop

ScienceSoft is ready to help you design and build the type of a payment app that fits the specifics of your business best.

A bank-based payment app

Employs existing banking infrastructure (a transaction processing system, a payment gateway) to process and settle digital payments in fiat currencies.

Best for: established traditional banks, neobanks.

A standalone payment app

Relies on non-banking payment processing infrastructure, enables fast and cost-effective funds transfer between the app’s users.

Best for: fintech startups focused on payments, including crypto startups.

A social-media-centric payment app

Provides a digital wallet embedded in the social media platform, allows for instant peer-to-peer payments between the social network users.

Best for: social media companies.

A mobile-OS-based payment app

Offers a digital wallet built upon a mobile OS for NFC- and QR-code-enabled offline payments and convenient online payments.

Best for: mobile device manufacturers.

Why Tap into the Payment App Market

An overall trend towards finance digitalization and cashless settlements, amplified by the growth of the ecommerce industry, drives the increasing popularity of online payments. The total value of digital payment transactions is anticipated to exceed $14 trillion by 2028, growing at a CAGR of 11.08%. This spurs the demand for convenient web and mobile apps enabling fast, secure digital payments and makes the payment app market a lucrative niche to step into.

Go-to monetization strategies for a payment app

  • Charging a transaction processing fee (a flat fee or a percentage of the payment amount).
  • Charging a fee for premium services, e.g., faster payment processing, higher transfer limits, or advanced security.
  • Applying a markup on the currency exchange rate for cross-border transactions.
  • Earning the interest on float accounts.
  • Selling in-app advertising.
  • Monetizing the app user data upon user consent.

A Sample Architecture of a Payment Application

Sample Architecture of a Payment Application - ScienceSoft

Payment applications ScienceSoft delivers typically comprise:

  • Web and/or mobile interface for end users to interact with the application (make and accept payments, check the account balance, monitor spend, etc.).
  • A payment processing system to verify a user’s personal and payment information, trigger funds settlement and control its progress.
  • PCI DSS-compliant data storage to ensure the security of cardholders’ sensitive data and enforce proper data retention and deletion policies.

To operate properly, a payment app needs to ensure a seamless payment data flow to the payment processing networks (e.g., the ACH network, SWIFT, VISA / MasterCard / American Express card network). Bank-based payment apps rely on direct integration between the bank’s existing processing system and the networks. Other payment apps usually employ banking APIs to integrate their payment processing system with a chosen acquiring bank, validate the required user information, and streamline its further transfer to the processing networks and other banks.

Note! Cryptocurrency payment processing requires integration with dedicated blockchain networks of the crypto coins that a payment app supports. ScienceSoft recommends employing ready-to-use cryptocurrency APIs (e.g., Coinbase API, CoinGate API) to streamline the connection of a P2P payment app to the required blockchain networks.

Additionally, a payment app can be integrated with an accounting system of the app owner to instantly record data on the received transaction fees. The solution may also be connected to the data analytics system to share relevant data required to analyze the app users’ payment behavior.

Key Features of a Payment Application

From ScienceSoft’s experience, companies looking to develop a payment application usually expect the solution to cover the following functionality:

Payments and money transfers

  • Sending and receiving domestic and cross-border payments, including recurring, split, and advance payments.
  • Real-time payments (RTP).
  • Support for various payment methods, including debit/credit cards, e-wallets, bank transfers, etc.
  • Multi-currency payments, including cryptocurrency payments.
  • Online and offline QR-code-based payments.
  • NFC-enabled onsite mobile payments.
  • P2P money transfers within the payment system’s network using an email address, a phone number, or an account ID of a money recipient.
Read all

Payment transactions tracking

  • A full history of payment transactions.
  • Real-time tracking of inbound and outbound payment transactions by status, period, amount, and more.
  • Configurable user notifications, e.g., on successful or failed automated payments, due payments, upcoming payment card expiry.
  • (for crypto payments) An immutable record of payment transactions in the blockchain ledger.
Read all

Spend management

  • Configurable budget and saving goals for a particular period (e.g., a week, a month, a quarter) or category (e.g., food, clothing, transportation, entertainment).
  • Real-time analysis of current vs. planned spend.
  • Alerts on actual expenses exceeding the pre-set threshold.
  • Automated generation of spend reports (by period, category, transaction amount, etc.).
Read all

Funds management

  • Filling up the account balance using a bank transfer or a debit/credit card.
  • Scheduled and ad hoc payouts to the bank account or a debit/credit card.
  • Automated updates of the account balance.
  • Automated conversion of the account balance and transferred amounts to the user-defined fiat currency or cryptocurrency.
  • Support for in-app currency exchange transactions.
  • Configurable dashboards with up-to-date currency exchange rates.
Read all

Account management for app users

  • Adding, saving, and updating personal/business info, billing details, including tax IDs, bank account and payment card details, etc.
  • Creating custom templates for recurring payments, such as utilities, rent, telecom, insurance, assigning a preferred payment method.
  • A digital assistant to help app users solve technical, transactional, security issues.
  • End-to-end audit trail of all account activities.
Read all

Billing and invoicing

  • Tracking paid and outstanding invoices.

For businesses:

  • Automatically generating and submitting multi-language invoices to customers to initiate the collection of due payments.
  • Automated generation of region-specific e-invoices.
  • Signing invoices using an electronic signature.

For customers:

  • In-app bill payments.
Read all

Ensuring robust payment app security

Cybercrime surrounding the field of e-payments reaches new heights year by year, and payment software is an attractive target for fraudsters. Identity deception, phishing, malware attacks, DDoS attacks are only few examples of cyber threats that, if not addressed properly, may result in funds theft and sensitive data breaches, leading to severe financial, reputational, and legal damage.

ScienceSoft implements powerful protective measures to secure your app against malicious actors:

Measures to Protect Payment App Security - ScienceSoft

  • Geography-based KYC/AML and OFAC verification for app users.
  • Multi-factor authentication, including biometric authentication (e.g., facial or fingerprint recognition).
  • Automated device identification and binding to user account.
  • Payment and user data encryption, including asymmetric encryption for crypto payments.
  • Transaction signing using a digital signature.
  • Password management.
  • Automated generation of one-time passwords (OTP) to verify a user for logging and transacting.
  • AI-powered detection of payment fraud, which is critical as financial fraud becomes more sophisticated.
  • Runtime application self-protection (RASP).
  • Authorization controls for APIs.
  • DDoS protection, firewalls, IDSs / IPSs, antivirus protection, EDR, SIEM, XDR, SOAR.

How to Build a Payment App

Below, ScienceSoft describes the essential steps we take to introduce reliable and secure payment applications tailored to the clients’ unique requirements.

Step 1.

Analysis and requirements engineering

Duration: 1–3 weeks

At this stage, ScienceSoft’s consultants:

  • Communicate with key project stakeholders to discuss the payment app vision or discuss payment handling needs.
  • Introduce a detailed list of requirements for the solution, which describes:
  • The type of a payment app.
  • The required platform to base a payment app on (web, mobile, or both).
  • Functional capabilities a payment app is expected to provide, e.g., support for particular payment methods (cards, bank transfer, e-wallet, etc.), currencies (fiat and crypto), payment models (e.g., recurring payments, split payments), and more.
  • The data the app should be able to process (customers’ personal information, credit card data, crypto wallet address, etc.).
  • Requirements for the app’s UX and UI.
  • Non-functional requirements, including security and compliance requirements (e.g., AML/KYC requirements to prevent payment fraud, PCI DSS requirements for secure credit card payments processing, and more).


Step 2.

Project planning

Duration: 1–2 weeks

The accurate planning of web and mobile payment app development can substantially reduce project timelines and prevent operational and financial risks. During this stage, ScienceSoft’s team:

  • Defines objectives, KPIs, and milestones for the project.
  • Determines project deliverables, duration, and budget.
  • Forms the project team and designs collaboration workflows.
  • Outlines possible project risks, defines a risk mitigation strategy and plan.
  • Estimates the expected TCO and ROI of the payment application.


Step 3.

Payment application design

Duration: 3–6 weeks

This step involves:

  • Designing the architecture of a payment app:
    • Creating a detailed description of how the app’s functional modules and a database should perform.
    • Determining integration approaches between the app’s components.
  • Introducing an optimal feature set for a payment application, including security and compliance features.
  • Designing UX and UI for the required user roles, such as individual users, corporate users, app admins:
    • Conducting UX research to understand the behavior of the app’s target audience.
    • Describing user interactions with the app, creating functional wireframes and content layouts.
    • UX prototyping.
    • Designing the visual appearance of the app and introducing UI mockups.
  • Providing a payment app integrations plan with the required payment processing networks, suggesting optimal ready-to-use integration solutions (particular open banking APIs, crypto APIs, etc.), if needed.


Step 4.

Tech stack selection

Duration: 2–3 weeks

When selecting techs and tools for payment app implementation, ScienceSoft adheres to the following practices:

  • We rely on best-performing technologies and tools to ensure the high quality of the application.
  • We compare possible techs and tools in the context of the client's priorities (e.g., prompt development, minimized project cost, etc.) and form an optimal tech stack with the client’s goals in mind.
  • We employ platforms, frameworks, and ready-made components where possible to streamline development and optimize project cost.


Step 5.

Payment application implementation

Duration: 5–8+ months, depending on the solution’s complexity

The implementation of a payment processing app with ScienceSoft usually includes the following stages:

1. Development

  • Establishing development and delivery automation environments (CI/CD, container orchestration, etc.).
  • Creating the server-side code of a payment app.
  • Developing role-based user interfaces.
  • Implementing a PCI DSS compliant database.
  • Performing unit tests in parallel with coding.

2. Integration with required systems

  • (for bank-based payment apps) App integration with a bank’s payment processing system.
  • (for other payment apps) App integration with the required payment processing networks using banking APIs and/or crypto APIs.

3. Quality assurance

  • Designing a test strategy, a test plan, test cases and checklists.
  • Writing and running automated test scripts, if relevant.
  • Conducting functional, including integration, and non-functional testing.
  • Fixing defects revealed during testing.

4. Deployment

  • Configuring the app’s infrastructure, backup and recovery procedures.
  • Implementing infrastructure security tools (authorization controls for APIs, DDoS protection algorithms, firewalls, IDSs / IPSs, etc.).
  • Deploying the payment application in the production environment.

Developing and launching an MVP helps promptly obtain end user feedback and rapidly adjust the app for higher user value. It allows for lower investments and faster payback from the app implementation. We can deliver an MVP of a custom payment app in 3–5 months and consistently grow it to the fully-featured solution with major releases every 2–3 weeks.

ScienceSoft's Senior Business Analyst and Financial and Banking IT Consultant

Step 6.

Support and evolution (optionally)

Duration: continuous

ScienceSoft offers continuous monitoring and optimization of the payment application to ensure its stable performance, compliance with relevant data security standards and regulations, and ability to provide smooth payment experience for end users. We can evolve the app by adding new features and perfecting its non-functional capabilities.



Consider Professional Services to Create a Payment App

ScienceSoft combines 25 years of experience in web development and 19 years – in mobile development with 19-year practice in financial IT to provide companies with:

Consulting on payment app development

  • Market and competition analysis.
  • Payment app conceptualization.
  • Defining product differentiation and a unique selling proposition (USP).
  • Optimal feature set, architecture design, UX and UI design, and tech stack.
  • A plan of integrations with the required systems.
  • Security and compliance consulting.
  • Providing an implementation roadmap, including a risk mitigation plan.
Go for consulting

End-to-end payment app implementation

  • Payment app idea productization and brand design.
  • Architecture design.
  • Web and mobile payment application development.
  • Developing APIs to expand the app’s integration capabilities.
  • App integration with the required systems.
  • Quality assurance.
  • Support and evolution of the app (optional).
Go for implementation

Why Build a Payment App with ScienceSoft

  • Since 2005 in payment software development.

  • Since 2003 in cybersecurity to ensure world-class protection of a payment application.
  • In-house compliance experts to guarantee payment app compliance with relevant global, country- and industry-specific standards and regulations.
  • Practical knowledge of 30+ industries, including BFSI, media, and telecoms.
  • A mature quality management system and customer data safety backed up by ISO 9001 and ISO 27001 certificates.
  • ScienceSoft is a 3-year champion in The Americas’ Fastest-Growing Companies rating by the Financial Times.
  • For the third consecutive year, IAOP features ScienceSoft in its Global Outsourcing 100, the list of the most trusted outsourcing service providers.

Typical Roles on ScienceSoft’s Payment App Development Teams

Project Manager

Creates a project plan, prioritizes the scope of work and monitors its execution, coordinates communication between the team members, reports the progress to the stakeholders.

Business Analyst

Analyzes needs and expectations of a client/target users and translates them into functional and non-functional requirements for the payment application.

Solution Architect

Designs the architecture of the payment application and its integration points with the required systems.

UX Designer

Performs UX research, designs user interactions with a payment application, conducts usability testing.

UI Designer

Creates the style of the user-facing interfaces and introduces a UI kit for user interface development.

Front-end Developer

Delivers UI of a payment app and fixes defects found by the QA team.

Back-end Developer

Delivers the code of the app’s back end, integrates the solution with relevant systems, and fixes defects found by the QA team.

DevOps Engineer

Containerizes payment app’s components, configures CI/CD pipelines for streamlined app development, testing, and release.

Quality Assurance Engineer

Creates and implements a test strategy, a test plan, and test cases to validate the quality of the payment app against the quality requirements defined in the project plan.

How to Make a Payment App Success: ScienceSoft's Featured Projects

Sourcing Models for Payment Application Development

Perks of Payment App Development with ScienceSoft

Prompt development

We guarantee a quick project start (1–2 weeks), frequent releases (every 2–3 weeks), and apply established Agile and DevOps practices to ensure app implementation on time and within budget.

We ensure application compliance with PCI DSS, AML/KYC regulations, CCPA, PSD2 and GDPR (for the EU), other relevant global, country- and industry-specific standards.

Transparent collaboration

We define custom sets of KPIs, track project progress, and submit regular reports to ensure service quality and transparency.

Fast payback

We rely on an iterative approach to payment app development to introduce the fundamental functions first and speed up payback.

Our Customers Say

We aimed to enhance our web platform and create a mobile app to facilitate POS financing. ScienceSoft offered the needed skills in back-end and front-end development, quality assurance, and Scrum management. Thanks to ScienceSoft, we achieved our project goals on time and within budget. They provided high-quality service and valuable tech insights that aligned well with our vision and specific needs.

Ascendas Business Solutions

The guys really cared about the online payment solution (a web app + iOS and Android mobile apps) they developed for my company and weren’t happy until they had it perfect. ScienceSoft were very patient with me when I changed my mind about requirements. They also ask the right questions and look for ways to improve on an idea. Their communication was really good, and they explained their approach to all aspects of the development.

For our project – building a Bitcoin mobile wallet on Cordova – we needed the assistance of a skilled mobile developer. ScienceSoft promptly provided us with an expert who joined our project team and quickly got up to speed with our Scrum processes. The developer quickly understood the existing code base and proceeded to modify and evolve it according to our requirements. Together, we released our app on time and on budget.

ScienceSoft’s Tech Stack for P2P Payment App Development

We know how to create a payment app for impeccable performance, full security, and seamless growth. In our projects, we usually rely on the following proven tools and technologies:

How Much It Costs To Make a Payment App

The costs of building a payment app vary greatly from case to case. Below, ScienceSoft lists the major factors that affect the project budget:

Core cost factors

  • The type of a payment app (determines the spend on integrations with payment processing networks).
  • The number and complexity of the app’s features.
  • The platform to base the app on (web, mobile, or both).
  • (for mobile payment apps) Supported mobile platforms (iOS, Android).
  • The number of user roles and specific UX and UI requirements for each role.
  • Performance, scalability, availability, security requirements for the app.

Operational cost factors

  • License fees for cloud services, ready-made app components (e.g., KYC/AML verification services, messaging services), integration components (banking APIs, crypto APIs), security tools.
  • Maintenance of PCI DSS compliance, including annual PCI audits.
  • Payment application support services.
Pricing Information

From ScienceSoft’s experience, developing a payment application may cost from $150,000 to $2,000,000+, the lower applying to a mobile payment app of average complexity and the upper – to a comprehensive payment app with an independent processing engine at its core.

Want to learn the cost of your payment app?

Get a free estimate

About ScienceSoft

ScienceSoft is a global IT consulting and software development company headquartered in McKinney, Texas. Since 2005, we help companies create reliable and secure payment apps. In our payment software development projects, we employ robust quality management and data security management systems backed up by ISO 9001 and ISO 27001 certifications. ScienceSoft's top priority is driving project success despite time and budget limitations and changing requirements.