Tutorial Understanding different APK structures and how to mod them

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Verified Modder
Verified Modder
Feb 2, 2021
Hello guys,
Today we gonna talk about the main topic about APKs. So, hopefully anyone who reads this tries to understand the information about this tutorial.

So let's jump to the topic!
In the Android world, there are different kinds of Apk files so many people are tucked in modding bcz they are unable to mod bcz they don't know the structure of the APK.

Types of Apk.

1)Apk files end with .apk (normal apk)
2)XApk files
3)Xapk file with the split library

4)Apks files


1)Apk files end with .apk (normal apk)

So in (.Apk) files we can again divide it to some parts they are

1) Games with open dlls (mostly Unity games)
2) Gams with Il2cpp lib (Protected Unity games)
3) Games without metadata (Only the lib)
4) Games with libUe4 (Unreal engine games {Harder to mod})

So let's talk about the first subtopic

1) Games with open dlls (mostly Unity games)

So if you open an apk and if you find .dll files in "assets/bin/Data/Managed" like shown in this picture that game belongs to this type.
These games (99%) are made using unity games so this kind of games are really easy to mod!


there is a tutorial about modding these types of games so you can find it there.

2) Games with Il2cpp lib (Protected Unity games)

So later unity decided to protect their game libs from hackers and modders and improve their security they made a new inception method called Il2cpp so as a result of day most of the games contain these kinds of libs.

If you go to "assets/bin/Data/Managed" you can't find dlls instead of that you will find 3 folders.
So these kinds of games are il2cpp games.


There is a tutorial made by me and pmt modder with a video tutorial so you can learn how to mod these kinds of games.

3) Games without metadata (Only the lib)

So these kinds of games are made from their own game engines or some are unity.
So this kind of games doesn't use a metadata file but use only the library file.

You can see there is no bin folder or sometimes there's no assets folder also.
(Inside the assets folder)


So these type of games you need to use IDA to mod.

4) Games with libUe4 (Unreal engine games {Harder to mod})

So this kind of games are really hard to mod because unreal games have it's own security so it's harder to mod. You can identify the unreal games like this.
Goto "lib/armeabi-v7a/" there you can find a lib called "libue4.so"


Still,I don't have a tutorial for this so sorry for that!


2)XApk files

So today many games are above 150 Mb. An apk's maximum size is 150mb because when the size of the apk gets bigger it means the time it takes to install it gets longer. This is why most games come with "OBB" files.
In your mobile phone's storage, you can see it.
Go to the file manager and chose "internal storage/Android/Obb"
You can see a couple of folders there so the obb file contains the games resources and its files to run the game.

An XAPK file is a package used to install Android apps on mobile devices. It is similar to the standard .APK format, but may contain other assets used by the app, such as an .OBB file, which stores graphics, media files, and other app data. XAPK files are used for distributing apps on third-party Android app download websites. They are not supported by Google Play.

If you have a xapk file open it then you can see like this!


So, install this kind of file rename the xapk file to .zip (ex:- pubg.xapk to pubg.zip)

Then copy the android folder to "Device storage", and install the apk.
Now you can see it is not hard to install xapk files.


3)Xapk file with the splited library.

So some xapk files do not contain a Android folder. Instead of that it contains 2 apk files like the following image;


So these types of games split the library and the apk. If you open the base apk there is no lib folder, but if you open the library apk there will only the lib folder.

4)Apks files

An APKS file is an APK set archive generated by bundletool, a utility used for creating and managing Android App Bundles (.AAB files). The archive, which is a compressed .ZIP file, that contains a set of .APK files. These are split based on device characteristics such as architecture, language, screen density, and other device features. Bundletool uses the files to install optimized versions of the app on devices based on the device profile.

For example;
These kinds of apks use different languages so if you open an apks file like a zip you can see it contain different kinds of language files. Games are not coming with this extension but some apps come with this extension.

So that's how you guys get enough knowledge on APK's and continue modding!

Still have questions?
Join my Discord for more information
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New member
Mar 21, 2022
can u mod critical ops game its il2cpp game its a online game and there is a mod menu already but that is outdated its 1.26 and upcoming version of the game will be 1.32 i dont know if values change by these updates but if not then plz mod this game or i can do the stuff that is in your awesome tutorial but i dont know how to find like aimbot radar or see though wall esp and i also dont know how to hook this with the mod menu there are tutorials of all this in the forum but its still a lota work but u know how to do it can u plz do it the fan base of this game is very high and a mod already exists he is not upgrading it probably cuz things have change a bit like there used to be obb but now ita a whole 800mb apk u can giv him the credit for the values and all and u can take this game mod forward with updates cuz someone have to keep updating the good work i mean i know its not that easy but u might figure it out plz at least try and eeply if possible i also added the game in request section the ios users have it and killing us the Android users but no one is doing it for Android help uss plzzz


New member
May 13, 2022
@DVAツ nice share bro..
But I have question about how about the game "APKS" without libgame.so / libil2cpp.so / libmain.so And metadata .
also I see on the asset folder because it's apks.

Well.. I see all your video bro, also I download it lolol for my learning

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