Payment Gateway Integration for Mobile and Web Apps

Payments Integration for a Web or Mobile App: Summary

Integration of payment functionality in a web or mobile application aims to help companies smoothly, quickly, and securely accept digital payments from customers.

Key project steps: Business needs analysis and requirements elicitation, integration conceptualization, project planning, tech stack selection, integration implementation and quality assurance, support and evolution of the integrated system.

Timelines: 2–5+ months, depending on the chosen approach to payment integration.

Cost: $20,000–$100,000 to integrate a market-available payment gateway, $100,000–$300,000 to build and integrate a custom payment gateway. Use our free calculator to estimate the cost for your case.

Team: a project manager, a business analyst, a solution architect, developers, a DevOps engineer, a QA engineer.

ScienceSoft provides all the necessary talents to help our clients smoothly integrate payments for their web and mobile applications. Our team's proven tech skills and multi-industry expertise ensure prompt and high-quality integration with minimal disruption to internal business processes.

Online Payment Gateway Overview

To enable payment functionality, your application should be integrated with an online payment gateway. Such software:

• Connects to a web and/or mobile application that hosts a checkout page to collect purchasing details, personal information, and payment data (e.g., credit card data) provided by customers.
• Encrypts sensitive data and transfers it securely to a payment processing system of an acquiring bank, an independent payment processing provider (e.g., PayPal, Stripe, Authorize.Net), or the company (in case of relying on in-house payment processing). The payment processing system verifies the customers’ personal and financial data and transmits transaction details to a payment processing network (e.g., a card network) that connects to the customer’s bank to finalize settlement.
• Integrates with an accounting system to instantly communicate data on successful payments and receive triggers to charge the recurring payments.

A Sample Architecture of Online Payment Gateway Integration by ScienceSoft

There are two main approaches to integrating a payment gateway with your application, each with its benefits and limitations. Here at ScienceSoft, we are ready to help you choose the optimal approach to meet your payment handling needs.

Apps That Will Benefit from Payments Integration

In web development since 1999 and in mobile development since 2005, ScienceSoft helps companies in 30+ industries design and build reliable web and mobile apps tailored to their business needs. Based on ScienceSoft’s experience, the following types of apps would benefit from the integrated payment functionality the most:

How to Integrate Payments for a Mobile or Web Application

During a typical payments integration process, ScienceSoft experts take the following steps:

Step #1. Conduct business analysis and requirements elicitation

Duration: 1–3 weeks.

ScienceSoft starts any payments integration project with a thorough analysis of a client’s needs and expectations. We closely collaborate with project stakeholders to collect the answers to the following key questions:

• What payment methods should the payment gateway support? (a credit/debit card, an e-wallet, crypto, etc.)
• In which regions should payments be available? (globally or in specific countries)
• What volume of transactions should the solution be able to process? (daily, monthly, during peak periods, etc.)
• Are there any specific requirements for the customers’ checkout experience? (in-app payments only or redirect is possible)

After that, ScienceSoft’s consultants analyze the company’s existing IT infrastructure and the applications to be integrated with an online payment gateway to understand their capabilities and constraints. Also, we define the data to be shared (customers’ personal information, credit card data, etc.), figure out how it should flow and whether it needs to be transformed into a different format.

One more important point to analyze is potential regulatory risks and compliance requirements. This helps ensure the online payment gateway will meet PCI DSS requirements for secure credit card payment processing, AML and KYC requirements to prevent payment fraud, other industry- and region-specific regulations.

Once the analysis is done, ScienceSoft’s consultants prepare a detailed list of requirements for the integration solution, which describes:

• All the payment capabilities the solution should provide.
• The required data inputs, outputs, and attributes of the online payment gateway.
• Non-functional requirements for the integrated system (availability, integrity, scalability, maintainability, performance, security, etc.).

Step #2. Conceptualize payment integration in the app

Duration: 2–5 weeks.

Upon forming a high-level vision, ScienceSoft proceeds with the design of a payments integration solution. This step involves making several important technical decisions:

1. Deciding on the preferred type of an online payment gateway to integrate:
   • a market-available payment gateway:
     • a hosted payment gateway.
     • a self-hosted white-label payment gateway.
   • a custom payment gateway.
2. (In case of opting for third-party software) Choosing an optimal prebuilt payment gateway according to the client’s specific criteria and business priorities. We at ScienceSoft perform a detailed comparative analysis of possible solutions to recommend the one that offers the required features and ensures economic feasibility.
3. Defining the appropriate payment integration pattern depending on the selected type of payment gateway:

• Embedding payment buttons and redirect scripts into the checkout interface.
• Relying on ready-to-use integration APIs provided with market-available online payment gateways.
• Designing custom APIs to integrate custom online payment gateways or smoothly connect OOTB solutions with existing customer-facing applications.

A payment gateway type and an integration pattern, as well as functional and non-functional requirements for the payment solution, provide a basis for designing the integration architecture. At this stage, ScienceSoft also designs a custom payment gateway and creates a custom UI of a checkout page, if required.

Step #3. Plan the project

Duration: 1–2 weeks.

During this stage, ScienceSoft introduces a detailed integration project plan, which defines:

• Project deliverables.
• Project duration and budget.
• Critical milestones, objectives, and KPIs for the project.
• Project-associated risks and the ways to mitigate them.
• Expected TCO and ROI of the integration solution.

Step #4. Choose an integration tech stack

Duration: 2–3 weeks.

ScienceSoft defines the techs and tools required for web and/or mobile payment gateway integration, relevant back-office systems (e.g., accounting software), and an external payment processing system. We compare various integration techs and tools in the context of the documented business requirements and select the optimal ones.

Step #5. Implement payment integration and conduct quality assurance

Duration: 2–8 weeks, depending on the chosen integration pattern (custom payment gateway development and integration may be significantly longer than integrating a market-available solution).

The implementation of payments integration with ScienceSoft usually covers:

1. Developing and deploying a custom web and/or mobile payment gateway (if required).
2. Depending on the chosen type of payment gateway and an integration pattern:
   • Developing and installing custom integration APIs.
   • Setting up ready-to-use APIs.
   • Building payment buttons, redirect scripts, webhooks, and other required components and incorporating them into the checkout interface.
3. Establishing further integrations with the required solutions (a web and/or a mobile app, a payment processing system, accounting software).
4. Implementing security tools (authorization controls for APIs, transaction validity confirmation mechanisms, DDoS protection algorithms, firewalls, IDSs / IPSs, DLP systems, etc.) to ensure the protection of the integrated system and the sensitive data it processes and stores.

ScienceSoft’s team performs quality assurance of each component of the solution in parallel with coding to eliminate possible vulnerabilities and logic errors and guarantee the proper functioning of all uni- or bidirectional queries between the connected applications.

Note: Before launching the payment features in your app, you need to establish a merchant account with a bank to receive customer payments. In the case of relying on a prebuilt payment gateway, you also need to establish a merchant account with a payment processor (e.g., PayPal, Stripe, Authorize.Net) to manage the received funds.

Prior to payment gateway implementation in the real environment, you need to achieve PCI DSS compliance. This is critical in the case of building a custom payment gateway or setting up a self-hosted OOTB solution.

Step #6. Provide after-launch support and evolution of the integrated system (optional)

Duration: continuous.

• Fixing payment gateway performance and scalability issues, if any.
• Adjusting the payments integration solution’s functionality to the changing business needs (e.g., adding new payment methods).
• Monitoring and maintaining payment gateway compliance with PCI DSS and other relevant data security standards and regulations.

Consider Professional Services to Integrate Payments for Your Application

In application integration since 1989 and in financial software development since 2005, ScienceSoft can help with:

Why integrate payments in the application with ScienceSoft

• Since 1989 in application integration services.
• Since 2005 in financial software development.
• Since 2003 in cybersecurity to ensure world-class protection of payments integration solutions.
• Practical knowledge of 30+ industries, including ecommerce, BFSI, healthcare, telecoms, professional services.
• Well-established Lean, Agile, and DevOps practices.
• A quick project start (1–2 weeks) and frequent releases (every 2–3 weeks).
• A mature quality management system and customer data security backed up by ISO 9001 and ISO 27001 certifications.
• ScienceSoft is a 3-year champion in The Americas’ Fastest-Growing Companies rating by the Financial Times.
• For the third year in a row, ScienceSoft secures its presence in the Global Outsourcing 100, the list of the most trusted outsourcing service providers carefully selected by IAOP.

Typical Roles in ScienceSoft’s Payments Integration Teams

NB! ScienceSoft is ready to provide additional talents, for example, UX and UI designers to design a checkout page for your application.

Sourcing Models for Payment Integration in the App

How Much Does It Cost to Integrate Payments in an App?

From ScienceSoft’s experience, each payment integration case is unique, so the cost factors vary for different customers. Below, we outline general factors that affect the cost and duration of payments integration projects.