A deep dive into Android 15’s move to 16KB pages, what it means for performance, and the step-by-step guide to ensure your app with native code is ready for the November 1st deadline.

As an Android developer, I love digging into the “why” behind the big architectural shifts in the platform. Sometimes, a change that seems obscure and low-level on the surface greatly impacts the user experience and our development process. The transition to a 16-kilobyte (KB) memory page size in Android 15 is one of those changes.

For years, Android has managed memory in 4KB chunks. But with modern devices shipping with more RAM than ever, that’s become inefficient. Starting November 1, 2025, Google Play will require all new apps and updates targeting Android 15 (API 35) or higher to be compatible with this new 16KB page size.

If your app is 100% Kotlin/Java, you can probably relax. But if your app uses native code (C/C++)—and you’d be surprised how many do, thanks to third-party SDKs—this is something you need to act on now.

Let’s break down what this change really means, why it’s a good thing, and walk through a clear, three-step plan to get your app ready.

The “Why”: What’s a Memory Page Anyway?

To understand the change, we need a simple mental model. Think of your phone’s physical RAM as one giant, shared warehouse. The memory for every single app is stored in this one chaotic space.

Your app, however, doesn’t see this mess. The Android OS gives your app a “magical map” (its virtual memory) that makes it believe it has its own private, perfectly organized warehouse. The OS acts as the “Warehouse Manager,” translating requests from your app’s private map to the actual location in the shared warehouse.

The Android OS acting as the Warehouse Manager

This manager doesn’t deal with individual bytes; that would be too slow. Instead, it manages memory in fixed-size blocks called pages. For all of Android’s history, that size has been 4KB. The new 16KB page size means the standard block of memory the OS works with is now four times bigger.

The Payoff: Why Bigger Pages Mean Better Performance 🚀

So why make this change? It all comes down to a piece of hardware in the CPU called the Translation Lookaside Buffer (TLB).

Think of the TLB as the Warehouse Manager’s pocket notepad. It’s a small, super-fast cache that stores the most recent memory lookups.

• A TLB Hit is when the requested memory location is in the notepad. This is incredibly fast.
• A TLB Miss is when it’s not, forcing a slow trip to the “master logbook” (the main page table in RAM).

What happens when the Translation Lookaside Buffer (TLB) has either a “Hit” or a “Miss”

The key is that the notepad (the TLB) has a fixed number of lines. With 16KB pages, each line on that notepad covers four times more memory. This concept is what I call “TLB Reach.”

A larger reach means fewer slow misses. This isn’t just theory; Google has the numbers to prove it:

• App Launch Time: 3.16% faster on average (up to 30% for some apps!)
• Power Consumption: 4.56% lower during launch.
• Camera Start-up: Up to 6.60% faster.

This is a fundamental optimization that makes the entire ecosystem more efficient.

The Impact: Will My App Crash?

This is where we get to the core of the issue for us developers. An app might crash if it uses native code (C/C++). This could be your own NDK code or, more commonly, a third-party SDK you’ve included.

The problem is Memory Alignment. An older native library might have been built with a hardcoded assumption that a new memory block starts every 4096 bytes. On a 16KB system, that address is now in the middle of a larger block.

The difference between the 4KB system and the 16KB system that could lead to alignment issues

When the OS sees the library trying to load there, it sees a “rule violation” and shuts down the operation to prevent memory corruption.

This is what a SIGSEGV crash in your Logcat is likely pointing to.

The Action Plan: Your 3-Step Guide to Compatibility

Alright, we understand the problem. The good news is that the fix is straightforward.

Step 1: Audit Your App

First, find out for sure if you’re using native code. The easiest way is with Android Studio’s APK Analyzer (Build > Analyze APK...). If you see a lib folder inside your APK, you have native code.

The presence of the “lib” folder indicates native code is present in your app

Keep an eye on your Build output, too. The new Lint checker in Android Studio will proactively warn you about non-aligned libraries it finds.

Step 2: Upgrade & Recompile

For most, the solution is to rebuild with modern tools.

• If you write your own C/C++ code, make sure you’re using Android Gradle Plugin 8.5.1+ and NDK r28+. These versions handle the 16KB alignment automatically.
• If the code comes from an SDK, check the library’s release notes and update to a version that is explicitly 16KB compatible.

Also, audit your native code for hardcoded page size assumptions.

BAD ❌

// Hardcoded assumption will crash!
#define PAGE_SIZE 4096
void* myBuffer = memalign(PAGE_SIZE, size);

GOOD ✅

// Ask the OS for the real page size
#include <unistd.h>
long pageSize = sysconf(_SC_PAGESIZE);
void* myBuffer = memalign(pageSize, size);

Step 3: Test & Validate

Don’t just build and hope. You must test. The easiest way is with the Android Emulator. When creating a new AVD, select a system image with “16KB Page Size” in its name for Android 15 or higher.

If you have a physical Pixel 8 or 9 series device, you can also enable a developer option to reboot into a native 16KB mode.

Workarounds and Future-Proofing

• The Escape Hatch: If you’re stuck on an older version of AGP (below 8.5.1), you can use a temporary workaround. Add useLegacyPackaging = true in your build.gradle‘s packagingOptions block to avoid installation issues.

android {
    packagingOptions {
        jniLibs {
            useLegacyPackaging = true
        }
    }
}

• For Android 16: To avoid a user-facing warning dialog on future OS versions, you can opt in to a compatibility mode by adding android:pageSizeCompat="true" to your AndroidManifest.xml.

<application android:pageSizeCompat="true" ...>

This article was previously published on proandroiddev.com.