What Is an API?
API stands for Application Programming Interface. In simple terms, an API is a messenger that allows different software applications to communicate with each other. According to Postman, APIs are the behind-the-scenes tools that make modern technology work by connecting services and simplifying data exchange.
The Restaurant Analogy
Think of an API like a waiter at a restaurant. You (the app) tell the waiter (the API) what you want from the menu. The waiter takes your order to the kitchen (another service), and brings back your food (the response). You never need to go into the kitchen yourself—the waiter handles all the communication. According to freeCodeCamp, this analogy perfectly captures how APIs work as intermediaries between systems.
How an API Request Works
Your App
Makes request
API
The messenger
Server
Processes & responds
Why Do Apps Need APIs?
According to AWS, APIs allow different software applications to communicate without knowing how the other works internally. This makes development faster, easier, and more efficient. Here is why APIs are essential for modern mobile app development.
Save Development Time
Why spend months building a mapping system when Google Maps API exists? APIs let you leverage years of engineering work instantly. Gartner predicts over 30% of new API demand will come from AI tools by 2026.
Access Complex Services
Processing payments requires PCI compliance and banking relationships. Using Stripe or PayPal APIs gives you secure payment processing without the regulatory burden.
Connect to External Data
Weather forecasts, stock prices, social media feeds—APIs provide real-time access to data you could never collect yourself. 83% of internet traffic flows through APIs.
Add AI Capabilities
Want ChatGPT-like features in your app? OpenAI and other AI APIs let you add intelligent features without building machine learning models. By 2026, 80%+ of enterprises will use AI APIs.
Build vs. API: Cost Comparison
| Feature | Build Yourself | Use API |
|---|---|---|
| Payment Processing | $500K+ (PCI compliance, banking) | 2.9% + $0.30/transaction |
| Mapping & Navigation | $1B+ (Google Maps cost) | $0.007/request (28K free/month) |
| Email Delivery | $50K+/year (servers, deliverability) | $0.001/email (SendGrid) |
| AI/ChatGPT Features | $100M+ (training models) | $0.002/1K tokens (GPT-4) |
Sources: Stripe, Google Maps Platform, OpenAI
How APIs Work: The Basics
According to IBM, APIs work through a simple request-response cycle. Your app sends a request to an API endpoint, the server processes it, and returns a response. The most common type is the REST API, used by 93.4% of developers according to Nordic APIs research.
REST APIs
Use HTTP methods (GET, POST, PUT, DELETE) to interact with data. Simple, lightweight, and flexible.
GET /api/users/123GraphQL
Request exactly the data you need in one query. 22.5% of developers now use GraphQL.
{ user(id: 123) { name } }WebSocket APIs
Two-way communication for live updates. Perfect for chat, gaming, and live data.
ws://api.example.comCommon HTTP Methods (REST)
Retrieve data
Get user profile, fetch product list
Create new data
Create account, submit order
Update existing data
Update profile, change settings
Remove data
Delete post, remove item from cart
Popular APIs for Mobile Apps
When building a mobile app, you will likely use several APIs. According to Devzery research, these are the most commonly integrated services.
Payment APIs
Accept payments securely
Maps & Location APIs
Navigation and geolocation
Google Maps
Most popular, 28K free requests/month
Mapbox
Customizable, 50K free requests
HERE
Enterprise-grade, used by BMW
Authentication APIs
User login and identity
Firebase
Google-backed, social login built-in
Supabase
Open-source, 4.5M+ developers
Auth0
Enterprise SSO, compliance-ready
Messaging
Twilio • SendGrid • OneSignal
Social Media
Facebook • Twitter • Instagram
Media & Storage
Cloudinary • AWS S3 • Imgix
Analytics
Mixpanel • Amplitude • Segment
AI & ML
OpenAI • Anthropic • Hugging Face
Backend
Supabase • Firebase • MongoDB
How No-Code Tools Handle APIs
The good news? You do not need to write code to use APIs in your app. Modern no-code app builders and AI platforms handle the technical complexity for you. According to 451 Research, 60% of custom apps are now built outside IT departments using these tools.
Traditional API Integration
- ✗Write authentication code
- ✗Handle API keys securely
- ✗Parse JSON responses
- ✗Handle errors and edge cases
- ✗Manage rate limits
No-Code/AI Integration
- ✓Pre-built integrations ready to use
- ✓Visual API connectors
- ✓Automatic data mapping
- ✓Built-in error handling
- ✓Describe what you want in plain English
APIs Made Simple with Natively
Natively handles API integrations automatically. Describe your app idea—like "I want users to pay for subscriptions and see their location on a map"—and the AI sets up Stripe and mapping APIs for you. With built-in Supabase integration, your app gets database, authentication, and storage APIs configured automatically.
API Security Basics
According to Nordic APIs, 91% of organizations experienced API security incidents in 2020, with malicious API traffic up 348%. Understanding basic security concepts helps you make better decisions when building your app.
API Keys
Unique identifiers that authenticate your app. Keep these secret—never expose them in client-side code or public repositories.
Use environment variables and server-side storage
HTTPS/SSL
All API communication should use HTTPS (encrypted). This prevents data from being intercepted during transmission.
Reputable APIs enforce HTTPS by default
Rate Limiting
APIs limit how many requests you can make per second/minute. This prevents abuse and ensures fair usage.
Handle rate limit errors gracefully in your app
Input Validation
Never trust data from APIs without validation. Malformed or malicious data can cause app crashes or security issues.
Modern no-code tools handle this automatically
Try It: Interactive API Explorer
See how APIs work in practice. This interactive demo shows how apps communicate with different types of services. Select an API category to see example requests and responses.
Select an API to explore:
Payment API
Process payments securely with Stripe
POST /v1/payment_intents{
"amount": 2000,
"currency": "usd",
"payment_method": "pm_card_visa",
"description": "App subscription"
}Click the button below to simulate an API call
Real-world uses:
E-commerce checkout, subscription billing, in-app purchases
How Natively handles this
Instead of writing this code yourself, simply describe what you want: "Add a payment screen where users can subscribe for $20/month"
Frequently Asked Questions
What is an API in simple terms?
An API (Application Programming Interface) is like a messenger that allows different software applications to talk to each other. Think of it as a waiter in a restaurant: you tell the waiter what you want, the waiter goes to the kitchen, and brings back your food. Similarly, an API takes your request, sends it to another system, and returns the response. This allows your app to access features like weather data, payment processing, or social media without building everything from scratch.
Why do apps need APIs?
Apps need APIs to access functionality that would be impossible or impractical to build themselves. For example, instead of building your own mapping system (which costs billions), your app can use the Google Maps API. Instead of processing credit cards directly (which requires PCI compliance), you can use Stripe or PayPal APIs. APIs save development time, reduce costs, and let you leverage world-class services. According to research, 90% of developers use APIs, with 83% of internet traffic coming from API-based services.
How do no-code tools handle API connections?
No-code and AI app builders simplify API connections by providing pre-built integrations or visual interfaces for connecting to services. Platforms like Natively handle API connections automatically when you describe what you want your app to do. For example, if you say you want payment processing, the AI sets up the Stripe integration for you. Other no-code tools offer drag-and-drop API connectors, visual authentication flows, and pre-configured webhooks that require no coding knowledge.
What are the most popular APIs for mobile apps?
The most popular APIs for mobile apps include: Payment APIs (Stripe with 8.1% market share, PayPal with 47.4% market share), Google Maps API for location services, Firebase for authentication and real-time databases, Twilio for SMS and messaging, social media APIs (Facebook, Twitter, Instagram) for login and sharing, OpenAI for AI capabilities, and cloud storage APIs like AWS S3 or Cloudinary for media. These APIs handle the heavy lifting so developers can focus on their app unique features.
Do I need to know coding to use APIs in my app?
No, you do not need coding knowledge to use APIs in your app if you use modern no-code or AI app builders. Platforms like Natively, FlutterFlow, and Bubble handle API integrations through visual interfaces or AI-powered setup. You simply describe what you want (like add payment processing) and the platform configures the API connection. However, understanding basic API concepts helps you make better decisions about which services to integrate and troubleshoot any issues that arise.