How to Create a Kiosk Application: Case-based Guide

Ever noticed how unattended payment terminals have transformed modern interactions? From cafes and retail stores to EV charging stations, these devices are now essential tools across countless industries. But creating a smooth, reliable user experience — one that also integrates seamlessly with business workflows — requires more than just hardware.

Today’s payment terminals need user-friendly, adaptable kiosk app development services that manage everything from processing transactions to delivering real-time data insights and customer support.

Android-based payment terminals have emerged as a versatile solution for such needs. By leveraging Android’s flexibility, businesses can create tailored apps that meet the unique demands of their environment, whether that means easy-to-navigate interfaces, fast transactions, or compatibility with other enterprise systems.

In this article, we’ll explore what goes into Android kiosk application development, covering hardware capabilities, design considerations, and development strategies that ensure these devices enhance the user experience — all while keeping security and usability at the forefront.

Looking to dive straight into our case-based insights?

Types of Android Payment Terminals

Android payment terminals come in different types, each suited to various business needs and ideal for a range of kiosks software development solutions.

• Android Kiosks. Android kiosks serve as self-service terminals, providing customers with streamlined access to services, digital wallet integration, and NFC equipment. These kiosks are often deployed in retail stores, transportation hubs, and hospitality settings, where they can improve efficiency and customer experience by enabling users to independently interact with intuitive, custom kiosk apps.
• Smart POS Terminals. Smart terminals combine the flexibility of Android POS with advanced payment features such as POS system compatibility, payment network integration, and support for P2P payments. Commonly used in industries like retail and restaurants, smartPOS terminals offer versatile functionality for both self-service and assisted transactions, enhancing user experience and transaction efficiency. These devices are designed for easy POS app development, allowing POS developers to create tailored solutions for diverse business needs.
• SoftPOS Terminals. SoftPOS (software POS) terminals allow businesses to turn Android devices into contactless payment systems, supporting NFC contactless payments without the need for dedicated POS hardware. Ideal for mobile settings like pop-up shops, softPOS terminals support digital wallet payments, dip NFC, and dip NFC contactless, providing a flexible, secure solution for businesses looking to simplify payments on the go and build kiosk application.
• ChromeOS Kiosks. In addition to Android-based solutions, Chrome kiosks are also used in certain business applications. With the ability to choose app extensions, and access to Chrome apps and web apps, ChromeOS provides a secure, full-screen experience ideal for web applications and interactions. Kiosks with Chrome version are often chosen in educational and enterprise settings for their integration with Google Workspace tools and strong security features, making them an excellent choice if you want to create your own kiosk app.

Key Features of Android Payment Terminals

Let’s discuss the features that make Android terminals valuable tools for businesses!

📌 As you see, payment terminal application development is a powerful tool that allows companies to limit devices to specific applications or functions, providing enhanced security and control.

Benefits of Android Kiosk Mode

Based on our extensive expertise in Android app development services, we can affirm that one of the most popular types of Android payment terminal apps is the kiosk mode app. Let’s explore the main benefits of using Android kiosk mode for business operations.

📌 These benefits make Android kiosk mode an invaluable tool for businesses aiming to implement secure, scalable, and efficient digital solutions for self-service and POS apps.

Interested in leveraging the benefits of Android kiosk mode for your business? Contact us to learn how we can develop a secure, efficient kiosk solution tailored to your needs.

Real-World Examples of Android-Based Payment Terminals

Next, we’ll look at two widespread Android-based payment terminals: Worldline Valina EP2 and Sunmi FT2, optimized for secure payment and enterprise use.

Worldline Valina EP2 Terminal Overview

The Worldline Valina EP2 is a compact, Android-based payment terminal designed for unattended environments such as parking lots and EV charging stations.

Some key specifications of Worldline Valina EP2 include:

• Rugged Design. The device features a scratch-resistant display, and it’s certified for vandal- and weather-proofing (IK09, IP65).
• Security Features. The terminal meets PCI PTS standards and supports P2PE encryption for secure transactions. ARM TrustZone technology provides additional processor-level security.
• Flexible Payments. It accepts all major payment methods including contactless, chip-based, and magnetic stripe cards.

Worldline’s Android-based system ensures compatibility with business strategies, allowing each company to build a kiosk application that extends its functionality beyond payment processing.

Sunmi K2 Mini Terminal Overview

The Sunmi K2 Mini is a versatile, Android-based self-service kiosk terminal designed for industries such as retail, hospitality, and transportation. Its standout features make it an ideal choice for businesses seeking a powerful yet compact solution for self-service interactions.

Some key specifications of Sunmi K2 Mini include:

• High-Resolution Touchscreen. Equipped with a 15.6" Full HD multi-touch display, the K2 Mini provides a user-friendly and engaging experience for customers. The screen is highly responsive, making it perfect for smooth, quick interactions.
• Connectivity and Peripheral Support. The terminal includes a range of connectivity options, such as Wi-Fi (2.4G/5GHz) and Bluetooth (supporting BLE), ensuring reliable and fast communication. It also features multiple USB ports, a LAN port, and additional peripherals for seamless integration with various payment and verification tools.
• Built-In Printer and Barcode Scanner. The K2 Mini includes a high-speed thermal printer, supporting both 58mm and 80mm paper rolls, ideal for generating receipts quickly. An integrated barcode scanner allows for 1D and 2D barcode and QR code scanning, enhancing its utility for payment processing and product scanning.
• Face Recognition Capabilities. For advanced user verification, the terminal supports facial recognition through a 3D structured light camera, which can be used for secure payments and membership verification.
• Powerful Hardware. Running on either a Qualcomm Snapdragon octa-core or Rockchip quad-core processor, with 2GB RAM and 16GB ROM (expandable via MicroSD), the K2 Mini offers robust performance for handling complex tasks efficiently.

The Sunmi K2 Mini is a comprehensive solution for companies looking to create kiosk app. With Android kiosk mode and customizability, the Sunmi K2 Mini offers a reliable, self-service experience for businesses that need to streamline customer interactions in high-traffic settings.

Comparison of Worldline Valina EP2 and SUNMI FT2 Terminals

Let’s compare both terminals to better understand their possible real-world applications.

📌 The comparison between the Worldline Valina EP2 and Sunmi K2 Mini highlights their unique strengths for various self-service applications, particularly in the context of kiosk development software.

Android-Based Payment Terminal Constraints

When developing kiosk mode applications in Android, especially for EV truck charging services, it's crucial to consider the limitations posed by the hardware of payment terminals.

Two key constraints affect both the visual design and user experience.

1. Small Display Size. Payment terminals for EV charging infrastructure usually have small screens compared to smartphones, necessitating a minimalist and user-friendly design. Simplified layouts with large, touch-friendly buttons for key actions such as "Start," "End," “Continue” or "Help" are essential. Clear, readable text with dynamic sizing ensures that critical information, like charging status or payment confirmation, remains legible. The interface should be streamlined to guide users through the process with minimal distractions.

Tip: Always conduct user testing to gather feedback on the interface's usability and ensure that the design meets their needs effectively.

2. Limited Color Reproduction. Payment terminals for EV charging infrastructure usually have restricted color capabilities, impacting the display of user interface elements. High-contrast color schemes, such as dark text on light backgrounds, improve readability in various lighting conditions. A simple color palette should be chosen, using distinct colors like green for success and red for errors. This helps ensure that important alerts and statuses are communicated.

Tip: Test your color choices in different lighting environments to ensure they are effective and easy to read in all scenarios, such as bright sunlight or low-light conditions.

Core App Functionality

The core features of Milence’s Android payment terminal application development focus on simplifying the charging process for EV truck drivers.

Let’s discuss its core functionality!

1. Payment Processing. The kiosk app supports payment systems, allowing users to pay using debit or credit cards. Pre-authorization ensures that the payment method is valid before starting the charging session. Secure payment handling is critical, ensuring that sensitive customer data is safe. The payment flow is designed to be seamless, automatically passing charging information to the station after successful payment.

Tip: Implement robust logging of payment processes to monitor and troubleshoot any payment issues that may arise, enhancing user confidence in the system. For instance, successful EV charging apps rely on seamless payment gateway integration in mobile application to ensure a smooth and secure transaction experience.

2. Monitoring Charging Status. Drivers need real-time updates on their charging session, including metrics such as energy consumption, battery state of charge, and charging duration. The app should display these updates clearly, allowing drivers to monitor their sessions and plan their schedules effectively.

Tip: Include visual indicators (like progress bars) for charging status to provide drivers with an intuitive understanding of how much charging is left, improving their overall experience.

3. Viewing Statistics. Detailed session statistics, such as total energy consumed, charging time, and final costs, are presented at the end of each session. Drivers can retrieve their receipts via QR codes, allowing for easy cost tracking and reporting.

Tip: Consider adding a summary of the charging session, so drivers can quickly reference their activity and expenses, enhancing user engagement.

4. Contacting Support. The app integrates multiple support options, including a hotline and FAQs, to help users resolve any issues. Multi-language support ensures accessibility for drivers across Europe, while clear error and success screens guide users through any difficulties.

Tip: Implement a live support option to provide immediate assistance, making the user experience smoother and more responsive to driver needs.

Security Considerations

Ensuring robust security is at the core of how to make a kiosk app for the Android payment terminal. Let’s discuss the essential security measures we implemented to ensure smooth and reliable EV charging services.

1. Integration with Third-Party Systems. The Milence app integrates with third-party systems, namely the native payment app and Milance API key to ensure seamless service delivery. This includes connecting to the Milence API for managing sessions and authorizing payments, and a third-party payment apps for processing transactions. Additionally, robust error handling is necessary to prevent crashes or vulnerabilities during communication failures, ensuring the app remains stable without exposing sensitive system details.

Tip: Regularly review and update third-party integrations to address potential security vulnerabilities and ensure compliance with evolving security standards.

2. Passing Non-Disturbance Testing (NDT). Before deployment, the smart kiosk application must pass Non-Disturbance Testing (NDT) to confirm its stability and security. NDT ensures that the app functions reliably under various conditions without compromising security. This includes verifying the application's compatibility with external services, such as the payment app and Milence APIs, and ensuring that it handles errors gracefully.

Tip: Schedule NDT at various stages of development to identify and resolve potential issues early, saving time and resources before final deployment.

3. Maintaining Financial Security. Security in kiosk applications is as critical as in other financial technology solutions, such as how to create online banking website. The Android-based kiosk app should use pre-authorization to secure payments before charging begins and encryption techniques like tokenization to protect sensitive data. It also ensures that error messages are generic to prevent exposing system vulnerabilities.

Tip: Regularly conduct security audits and penetration testing to identify and mitigate potential vulnerabilities, ensuring that financial data remains secure against evolving threats.

Project Kickoff

Partnering with Stormotion, an experienced EV charging app development company, was crucial for meeting Milence’s objectives and ensuring a reliable user experience.

When Milence approached us to develop a kiosk app for their Android payment terminals, we knew that building a seamless user experience would mean navigating specific constraints and collaborating closely with the client from day one. Milence had a clear objective: to create a secure, intuitive app allowing EV truck drivers to manage charging sessions, view essential statistics, and reach support when needed.

As with all our IoT projects, our Project Manager, Uliana Veretko, requested the Android payment device and two test payment cards (Visa and MasterCard) to develop payment terminals app and conduct real-world testing. This allowed us to create, iterate, and refine the app directly on the device, ensuring it functioned reliably in a real-world environment.

Over the next 43 weeks, our five-person team — comprising a Project Manager, two Android Developers, a UX/UI Designer, and a QA Engineer — dedicated themselves to delivering an app that was both robust and highly user-focused.

Looking to develop a custom Android kiosk application for your business needs? Contact us to discuss how our development services can help you build a scalable, secure, and user-friendly app.

Tech Stack Choices for Kiosk App Development on Payment Terminals

Challenge #1: Finding the right balance between performance and security was crucial for developing a responsive Android kiosk app tailored to EV charging services.

Choosing the right technology stack is pivotal for a payment terminal application developer to create a secure and responsive Android payment app, especially one tailored to EV charging services.

Our tech stack enabled real-time interactions with charging stations, secure payment processing, and seamless third-party integrations while maintaining a smooth user experience on Android hardware.

Click Charging Connector

The "Clicking a Connector" feature, integral to our Android kiosk application development, lets drivers select the appropriate connector for charging by showing all available options. Different actions occur based on the selected connector’s status:

• Available: Prompts the user to plug in.
• Connected: Displays session details.
• Charging: Shows the session overview.
• Reserved or Unavailable: Shows an error screen with a “back” button.

This feature ensures that drivers can easily initiate charging sessions by identifying the right connector.

When we choose the connector, we call this function:

Check the Session Information

The "Check the Session Information" feature provides drivers with real-time updates on their active charging sessions directly on the Android-based payment terminal. By selecting the icon for the connected charging session, users can easily monitor key metrics such as battery status, charging power, and remaining time.

As part of our efforts to build kiosk app functionality, session information displays on the screen and refreshes regularly to keep users informed at every stage.

Payment Tap Screens

The "Payment Tap Screens" feature initiates a pre-authorization process to secure funds for the upcoming session. A reservation amount displays on the screen along with a card tap icon, allowing drivers to pre-authorize payment securely through the terminal. If successful, the user sees a confirmation screen; if unsuccessful, an error screen appears, keeping the driver informed of payment status every step of the way.

Localization

The “Localization” feature supports multiple languages, enabling drivers across different regions to navigate the interface with ease. This feature enhances accessibility by offering options in English, German, French, Dutch, Romanian, Polish, Spanish, Russian, and Italian.

A default language selection is set to English, but localization requires extra care to ensure translations fit within the UI constraints and are displayed correctly across languages. We’ll talk about the design constraints in the next section.

Here’s how our UI/UX designer, Iryna Ponomarenko, tackled the unique design challenges.

UX/UI Challenges

The terminal’s small screen size presented one of the biggest design challenges when we set out to build kiosk application. Our company needed to adjust element sizes, font styles, and layouts to maintain readability, even at a viewing distance of about half a meter.

Additionally, the terminal’s low-contrast display matrix and limited color reproduction meant that some shades weren’t visible or sufficiently distinct. We approached this by testing various color schemes and contrast levels directly on the terminal, optimizing the final design to ensure each element remained clear and visible under different lighting conditions.

Localization

Localizing the app for multiple languages — including those with longer phrases and non-Latin scripts — introduced further challenges. To avoid breaking the layout, we adapted font sizes and rephrased certain terms for compactness.

Additionally, customizing the Cyrillic font to fit the terminal’s display properly was essential to create kiosk app that blended seamlessly into the interface. This adaptability ensured that the Android app maintained its readability and functionality across all supported languages.

While the client’s backend developer adjusted values, our QA Engineer, Ostap Shtypuk, conducted real-time testing to ensure consistent feature performance.

This process included:

1. Security and Coverage Testing: Verifying compliance with security protocols to protect sensitive information.
2. Localization Testing: Given the terminal’s compact Android 4.4 display, we tested the display of information in multiple languages, adapting font sizes and shortening phrases as needed to fit the screen.
3. Interruption Testing: By simulating internet outages, we ensured the app’s stability and responsiveness under network disruptions, enabling smooth recovery when connections resumed.

🗂️ How Stormotion Helped Milence?

Our collaboration with Milence resulted in a robust, user-friendly Android app that streamlines the EV charging experience for drivers of heavy-duty trucks. Through focused design adaptability, agile development, and rigorous testing, we delivered a secure, scalable solution tailored to the constraints of payment terminals.

The kiosk app’s intuitive interface, real-time session tracking, and reliable pre-authorization process now support Milence’s mission to provide accessible, efficient charging infrastructure across Europe.

With scalability built into the app, Milence can easily adapt to future updates and features as they continue to expand. Our partnership in how to make a kiosk app enabled the company to bridge the gap between hardware limitations and user expectations, delivering an app that not only meets their needs today but is also prepared for the future.

The upcoming video feedback from Milence will highlight the project's impact and success, showcasing the value of this collaboration.