Why SDK Bloat is Slowing Down Your App and How to Fix It

Ever wondered why your app is sluggish, even on high-end devices? You may have faced SDK bloating—unnecessary third-party integrations weighing down the performance. Here’s how to fix it.

SDK bloat occurs when an app becomes excessively resource-intensive due to multiple third-party SDKs, especially redundant or poorly optimized ones (e.g., analytics, ads, social media SDKs).

Each SDK added to the app brings its own code and features, resulting in increased consumption of resources such as memory, network, CPU, and disk space. This can lead to an increased app size, unchecked background processes, network latencies, and slower overall performance.

Now that we've identified SDK bloat, let's explore the key reasons it affects app performance:

1 - Excessive Background Processes and Network Issues

Excessive processes running in the background and resource contention caused by bloated SDKs can lead to UI freezes, frame drops, ANR (Application Not Responding) errors, and increased latency, resulting in your app taking a performance hit.  Plus, there’s a significant drop in network performance due to increased and unnecessary network and API calls, resulting in slow app speeds.

Also Read: SDK vs. APIs: What’s the Difference and When to Use Each?

2 - Slower Execution Time for Abstracted Code 

Since SDKs are geared towards offering pre-built developer toolkits, they typically come along with a lot of code that’re abstracted for easy usage. As a result, apps are forced to execute huge volumes of code instructions to work through these abstractions to function as intended, thus taking up more system resources. 

3 - Feature (or Scope) Creep

Feature creep is a term often used in the context of software when providers keep adding too much or overly complex features to software, often without clear necessity. The same applies to SDKs. And this leads to larger, more complex SDKs with extended and oftentimes covering unnecessary scopes that consume more resources when integrated into apps, resulting in SDK bloat and slow performance.

4 - Dependency Hell

Since most SDKs themselves rely on external services, code libraries, APIs, and several other tooling to function correctly, their dependencies trickle down to your apps. If issues or conflicts arise in the components that make up the SDKs, these get compounded and drilled down to your apps, leading to sluggish performance.

Also Read: Why Unstable SDKs Cause More Bugs Than You Think

5 - Excessive Runtime Memory Consumption 

Excess SDK code increases your app's RAM usage, slowing performance. This leads to slower memory access. On devices with limited RAM, it can trigger memory swapping (thrashing), thus directly affecting your app's performance.

6 - Increased CPU Cycle Overhead

Unused code during SDK bloats often contributes to CPU overhead. This pushes the system to take longer for instruction loading (fetching data from a specific memory location) and branch prediction (when compilers have to anticipate which conditional statement to follow), leading to slower code execution times and reduced app responsiveness.

Also Read: How to Test Third-Party SDKs for Performance & Security Risks

7 - Improper Main Thread Management 

Many SDKs, particularly those performing network operations, disk I/O, or complex computations, may execute these tasks on the app's main thread. With SDK bloats, there are increased chances of the main thread slowing down or even getting blocked. Plus, poorly written SDKs that miss out on the proper usage of async code, worker threads, or optimized thread management lead to slow app performance. 

Also Read: Common Developer Mistakes While Integrating SDKs

8 - Garbage Collection Pauses

In managed languages (like Java, JavaScript, and others that rely on their runtime environment for memory management and garbage collection), SDK bloats contribute to a larger object (class) graph, thus increasing the frequency and duration of garbage collection pauses. This can cause noticeable stutters and interruptions in your app.

9 - Cache Misses and Pipeline Stalls

The increased code complexity due to SDK bloats can also lead to more frequent:

• Cache Misses - When the CPU needs to execute an instruction (or data) that is not currently stored in the fast instruction cache, forcing it to retrieve it from slower main memory, slowing down execution
• CPU Pipeline Stalls – When the CPU's pipeline, which allows it to process multiple instructions simultaneously, is forced to pause (or pipeline stall) due to dependencies or resource conflicts, reducing overall processing speed.

These issues can lead to reduced data throughput rates and slow code executions.

Practical ways that you can use to fix SDK bloats:

Fix 1 - Perform Thorough SDK Audit  

Start things off by creating a list of all SDKs that your app uses. In the audit run, document:

1. Purpose — Include details of why an SDK is included and what functionalities it's offering for your app.
2. SDK Versions — Note the existing version of the SDKs and see if any new versions, fixes, or patches are available from the providers.
3. Redundant or Unused SDKs — Identify SDKs that offer overlapping functionalities or those that are no longer in use.

What you should do:

Fix 2 - Use Native Code Whenever Possible  

For certain functionalities, whenever possible, consider writing native code instead of always relying on third-party SDKs. This allows your apps to work with more efficient, cleaner, and stable code that you’ve full control over. Besides this, fewer external libraries also mean leaner apps, less SDK bloat, and better performance.

What you should do:

Assess which SDK functionalities can be replaced with native code without massive development overheads.

Examples

Fix 3 - Monitor Performance Metrics   

Using profiling tools is one of the go-to ways to understand how SDKs are impacting your app performance. And this comes really handy while fixing bloating issues. 

What you should do:

Fix 4 - Optimize Code: w/ Lazy Loading, Async Patterns, and Data Optimization Techniques 

Consider the following code optimization techniques to fix SDK bloats:

Lazy Loading

• Conditional Initialization — Consider writing conditionals for code to initialize SDKs based on specific user actions or app states. For example, initialize a social sharing SDK only when the user taps the share button.

Example Code in Kotlin

if (userClickedShare) {
      SocialMediaSDK.initialize()
  }

• Background Thread Initialization — If SDK initialization is time-consuming, consider offloading it on a background or worker thread to avoid blocking the main thread during app startup.

Async Operations and Patterns

• Coroutine/Async-Await Patterns — Use async patterns, such as coroutines (Kotlin) or async/await (Swift, JavaScript), to simplify writing async SDK code without sacrificing readability.

Example Code using Coroutine in Kotlin

CoroutineScope(Dispatchers.IO).launch {
      val result = withContext(Dispatchers.Main) {
          SDK.performNetworkOperation()
      }
      // Update UI with result
  }

• Thread Pools — Use thread pools to efficiently manage background tasks and avoid creating excessive threads.
• Reactive Programming — Consider using reactive programming libraries (e.g., RxJava, RxSwift, and RxAndroid) to handle async events and data streams.

Data Optimization Techniques

• Serialization — Consider using efficient data serialization formats like Protocol Buffers to reduce data size and improve parsing speeds. 

Example Scenario: An SDK sends large amounts of data to a server.

What You Should Do: Instead of JSON, use protocol buffers to reduce the size of the data being sent.

• Caching — Implement data caching mechanisms to reduce redundant network requests and improve data retrieval speed.

Example Scenario: An SDK fetches data from a remote server that rarely changes.

What You Should Do:

Fix 5 - Manage Dependencies    

Finally, consider managing your SDKs and libraries with tools like Gradle build tool (Android) or CocoaPods (Swift for iOS) to fix bloating issues. With such tools, you can ensure:

• Version Control — Allows you to pin specific SDK versions to prevent unexpected size increases from auto-updates.
• Conflict Resolution — Enables you to resolve dependency conflicts to avoid redundant libraries and prevent bloat.
• Granular Dependency — With this, you can implement logic for importing only the needed modules of SDKs instead of the entire SDK.

Additional Considerations

• Dependency Locking — Use dependency locking mechanisms (e.g., package-lock.json, Podfile.lock, gradle.lockfile) to ensure consistent builds across different environments
• Extract Only What’s Necessary — If an SDK has a very small portion of code that you need, see if it is possible to extract that code into your purposes, removing the entire SDK.
• Replace Heavy Dependencies with Lightweight Alternatives — Research if there are smaller and more lightweight libraries that can replace heavy ones.