What Is the Cost of Integrating a Payment Gateway to a Website or Mobile App

7 min readNov 10, 2021

Most people today use on-site or in-app payments. Therefore, if you want your product to be not only of high quality but also really convenient, we recommend that you integrate the payment system at the stage of MVP development. How to integrate API correctly and what you should remember, we will talk about in this article.

What Is a Payment Gateway?

For banking, data storage, and direct transactions, you need payment gateways. They are services provided by third parties and authorized by banking systems. For example, a wide range of features is provided by PayPal and Stripe, all of which can be integrated into a custom application, ensuring the safety and reliability of all transactions. For such benefits, a commission or percentage of each transaction will be charged.

If for the user everything happens in a couple of seconds, then behind the scenes a series of operations takes place, in accordance with the rules established by banks and payment systems.

Thus, a gateway is primarily a special infrastructure that allows electronic transactions to be carried out on behalf of various suppliers. They take full responsibility for transferring data to financial institutions, tracking transactions, and guaranteeing the safety of customers. Thus, companies do not have to worry about storing their customers’ data.

Integrating a payment system is not that difficult, there are a huge number of free open-source software development kits (SDKs), as well as clear instructions, code samples, and all the necessary development tools. This is also convenient for developers because they will definitely comply with all strict rules and specifications. It is important to remember that requirements and specifications differ depending on the operating system chosen (Android or iOS), as well as for the applied approach to development (native or cross-platform).

How Does a Payment API Work?

Since the payment gateway is the main detail in the electronic payment processing system. It is through him that the client information is sent and the transaction is processed.

The architecture of a payment gateway API differs depending on its application. For example, the payment gateway of an online store and a portal are two different things. For example, gateways used for online payments require a payment request API that allows the site to interact with the underlying payment processing network. But the gateway in the store focuses on the use of POS terminals, which, when connected to a payment processing network in an electronic way, use the Internet or a telephone line.

The Importance of Payment API Integration for Business

Not everyone understands the importance of payment API integration for business. Let’s start with a basic concept of API: An API (aka Application Programming Interface) is intended to be used by one program by another. This is not software in the classical sense, it is closer to code that optimizes processes. In addition, APIs allow several programs to interact with each other at once. This optimization and significant acceleration not only improves service quality but also increases business agility. In addition, the use of ready-made solutions increases the security of processes, which is a critical factor when working with personal data.

The optimal solution is always to use custom fintech solutions and ready-made APIs. With a well-written API, you can get long-term benefits and a high level of flexibility. API integration is always quite simple and obvious for developers, which allows them to adapt to their needs.

So, for the banking industry, APIs provide a completely customizable experience, so adding new features will be simplified. APIs also simplify everything by speeding up user verification and fighting fraud.

How to Integrate a Payment API in Online Platforms?

One of the main difficulties in choosing a payment gateway is choosing the right one for your individual case. Each gateway has its own terms of use transaction fee.

Let’s consider the basic scheme of integrating a gateway to a website using the Stripe payment API as an example. You can do it quickly and professionally using binary UI components.

1. Install Stripe elements from Stripe.js

The uploaded script must be uploaded not only to the order page, but also to other pages. Don’t forget to replace the random API keys with your own.

2. Create a payment form

The components created by Stripe UI will be indexed and collect all the necessary information about customers and their banking data. You will be given a constructor to create a simple and understandable form.

3. Create a security token

All data collected about payment will be converted into special markers, so you need to take care of event processing.

4. Uploading the marker and the rest of the form to the server

To do this, you will need to create and load a special token into your code.

SDK Integration Features for Mobile Apps

When adding a mobile app payment gateway, it is important to keep in mind not only the technical but also the business requirements of your product. You should also take into account all the features of the integration of gateways for Android and iOS.

Start by identifying the basic shopping methods, not just cards, but also Google / Apple Pay, PayPal, Samsung Pay, Venmo, Weepay, and so on. A large selection always gives the best user experience. Most gateways can be added directly from the official websites of payment systems.

In addition to differences in the list of services provided by different SDKs, the requirements for the product itself may also differ. For example, there may be some problems based on the framework you are using.

Before starting to connect the provider, the business analyst needs to conduct research and weigh all the risks. We also recommend contacting the provider and discussing all the nuances that interest you. The beginning of cooperation is usually marked by the conclusion of a large agreement indicating all the nuances and aspects.

Also, the provider can assist in setting up trading accounts and assets at each stage of the payment gateway integration.

What Are the Main Payment Methods API?

By using the Payment Methods API, you can accept multiple payment methods through a single API. In this case, an object called PaymentMethod includes all the information about how the payment was made. In this case, a combination of PaymentMethod: with PaymentIntent is possible to accept payments.

Top 3 Payment Gateway Providers

Let’s take a look at some of the most popular gateway providers that are most common in different projects.

1. Stripe API

This is one of the most popular services, which provides high guarantees for the security of operations and allows you to use a large number of functions. Stripe API key features include accepting digital payments, tracking user accounts, sending invoices, and managing subscriptions.

Stripe payment gateway charges a 2.9% fee + $ 0.30 per payment.

2. Amazon Pay

Amazon Pay is a convenient gateway that allows users to use all of the payment information they have previously saved in their Amazon account.

Amazon Payment methods charges a transaction fee and separately applies an internal processing fee of 2.9% plus $ 0.30 authorization fee.

3. PayPal

PayPal is one of the most common systems along with Stripe. It stores all credit card and bank account information on trusted servers. The security and ease of use make the PayPal API key a great choice.

In terms of cost, Paypal charges 2.9% + $ 0.30 per transaction.

How Much Does It Cost to Integrate Payment API?

The API pricing and cost of integrating payment systems usually depends on many factors. The set of functions that you will connect to the application has a big influence on the cost. Basic functions include accepting and rejecting payments, and additional ones, for example, processing refunds.

The location and level of the developers also largely determine the final check. On average, integrating a payment gateway into Android and iOS will cost about $ 3000.

TopDevs Case: Payment API Integration

The TopDevs portfolio also contains a case of work with the integration of payment systems. We are talking about the Gerasyanov platform of inclusive health improvement for human well-being. Each payment platform user gets access to the knowledge base, calendar of events, and so on. They can also pay for participation in events and training by paying for everything directly in the applications.

The Tech Stack of the application looked like this:

Swift
Kotlin
Vue.JS
Laravel

The TopDevs team took over the full development cycle, thinking over the functions and developing the application from scratch.

Another case for working with payment systems is a shell for using Stripe, called Payment system 24/7. The software/application is great for both individuals and businesses, allowing them to get the main benefits of the system without much difficulty. This is a service for charging payment for offline services at any time for two IOS and Android (web and mobile).

Final Words

A payment gateway is a must for all commercial applications. If you want to sell services and/or goods, you will need to decide and connect the payment system.

Choose the mobile app SDK of existing payment options of gateways that can help you solve your business needs. Despite the simplicity of connecting payment systems, it is better to entrust SDK integration to professional developers.