GET and POST requests in Android Kotlin - Build, Publish & Deploy

Build & Publish - GET and POST requests

Performance Impact of GET and POST Requests

Network requests like GET and POST affect app speed and battery. Slow or large requests can cause UI delays and drop frames below 60fps. Excessive memory use happens if responses are large or not handled well. Battery drains faster with frequent or heavy data transfers.

💻

How to Optimize GET and POST Requests for 60fps Rendering

Use asynchronous calls with Kotlin coroutines to avoid blocking the main thread. Cache responses when possible to reduce network calls. Compress request and response data to save bandwidth. Limit request size and avoid unnecessary data. Use efficient JSON parsing libraries. Cancel requests if the user navigates away.

Impact on App Bundle Size and Startup Time

Network code libraries like Retrofit or OkHttp add a few MBs to the app size, usually under 5MB. Keep dependencies minimal to avoid bloating. Startup time is mostly unaffected unless you preload data synchronously. Lazy load data after startup to keep app launch fast.

iOS vs Android Differences for GET and POST Requests

Android uses libraries like OkHttp and Retrofit for HTTP calls. iOS uses URLSession. Both support async calls and background transfers. Android requires INTERNET permission in the manifest; iOS requires App Transport Security settings for non-HTTPS. Error handling and retry logic differ slightly due to platform APIs.

Relevant Store Review Guidelines and Requirements

• Ensure user data sent via POST is secure (use HTTPS).
• Follow privacy policies for data collection and transmission.
• Do not send sensitive data without user consent.
• Handle network errors gracefully to avoid crashes.
• Comply with platform-specific network usage policies.

Your App Takes 5 Seconds to Load This Screen. What's Likely Wrong?

Probably the app is making synchronous network calls on the main thread, blocking UI rendering. Or it is loading large data without caching or pagination. Another cause could be uncompressed or excessive data transfer causing slow responses.

Key Result

Efficient use of asynchronous GET and POST requests with proper caching and compression ensures smooth 60fps UI, minimal battery drain, and fast app startup. Use platform-specific best practices and secure data transmission to meet store guidelines.

Practice

1. What is the main purpose of a GET request in Android Kotlin networking?

easy

A. To fetch data from a server

B. To send data to a server

C. To update the UI thread

D. To store data locally

Solution

1. Step 1: Understand GET request purpose

   A GET request is used to retrieve or fetch data from a server without changing any data on the server.

2. Step 2: Compare with other request types

   POST requests send data to the server, unlike GET which only fetches data.

3. Final Answer:

   To fetch data from a server -> Option A

4. Quick Check:

   GET = fetch data [OK]

Hint: GET fetches data; POST sends data [OK]

Common Mistakes:

• Confusing GET with POST request purpose
• Thinking GET modifies server data
• Mixing UI updates with network requests

2. Which of the following is the correct way to start a POST request using Kotlin's HttpURLConnection?

easy

A. connection.requestMethod = "GET"

B. connection.requestMethod = "POST"

C. connection.method = "POST"

D. connection.setRequestMethod("GET")

Solution

1. Step 1: Identify correct property for request method

   In Kotlin, HttpURLConnection uses requestMethod property to set the HTTP method.

2. Step 2: Confirm correct method value for POST

   To make a POST request, set requestMethod to "POST" exactly.

3. Final Answer:

   connection.requestMethod = "POST" -> Option B

4. Quick Check:

   POST method set by requestMethod = "POST" [OK]

Hint: Use requestMethod property with "POST" string [OK]

Common Mistakes:

• Using wrong property name like method
• Setting GET instead of POST
• Using Java-style setRequestMethod() in Kotlin

3. What will be the output of this Kotlin code snippet when making a GET request?

val url = URL("https://example.com/data")
val connection = url.openConnection() as HttpURLConnection
connection.requestMethod = "GET"
val responseCode = connection.responseCode
println(responseCode)

medium

A. 500

B. 404

C. 200

D. Compilation error

Solution

1. Step 1: Understand the code flow

   The code opens a connection to the URL and sets the method to GET, then reads the response code from the server.

2. Step 2: Predict typical HTTP response code

   Assuming the URL is valid and reachable, a successful GET request returns HTTP status code 200.

3. Final Answer:

   200 -> Option C

4. Quick Check:

   Successful GET returns 200 [OK]

Hint: 200 means OK response from server [OK]

Common Mistakes:

• Assuming responseCode is a string
• Confusing 404 (not found) with success
• Thinking code will not compile

4. Identify the error in this Kotlin code snippet for sending a POST request:

val url = URL("https://example.com/api")
val connection = url.openConnection() as HttpURLConnection
connection.requestMethod = "POST"
val outputStream = connection.outputStream
outputStream.write("data=hello".toByteArray())
outputStream.flush()
outputStream.close()

medium

A. Missing setting connection.doOutput = true

B. Using write() instead of writeBytes()

C. Incorrect requestMethod value

D. Not reading the response code

Solution

1. Step 1: Check POST request setup

   For POST requests, doOutput must be set to true to send data in the request body.

2. Step 2: Identify missing property

   The code does not set connection.doOutput = true, so writing to outputStream will fail or not send data.

3. Final Answer:

   Missing setting connection.doOutput = true -> Option A

4. Quick Check:

   doOutput = true needed for POST body [OK]

Hint: Set doOutput true before writing POST data [OK]

Common Mistakes:

• Forgetting doOutput = true for POST
• Confusing write() method usage
• Ignoring response reading after POST

5. You want to send JSON data in a POST request using Kotlin. Which sequence correctly sets up the connection and sends the JSON string {"name":"John"}?

hard

A. Set requestMethod to "GET", write JSON bytes to outputStream, set doOutput = true

B. Set requestMethod to "POST", set doOutput = false, write JSON string directly to connection

C. Set requestMethod to "POST", write JSON bytes to outputStream without setting doOutput, set Content-Type header to "text/plain"

D. Set requestMethod to "POST", set doOutput = true, set Content-Type header to "application/json", write JSON bytes to outputStream

Solution

1. Step 1: Correct HTTP method and output setup

   For sending data, requestMethod must be "POST" and doOutput must be true to allow writing data.

2. Step 2: Set proper headers and write data

   Content-Type header should be "application/json" to indicate JSON data. Then write JSON bytes to outputStream.

3. Final Answer:

   Set requestMethod to "POST", set doOutput = true, set Content-Type header to "application/json", write JSON bytes to outputStream -> Option D

4. Quick Check:

   POST + doOutput + JSON header + write bytes [OK]

Hint: POST JSON needs doOutput true and JSON content-type [OK]

Common Mistakes:

• Using GET method to send data
• Not setting Content-Type header correctly
• Forgetting doOutput = true