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I know that .odex files are optimized .dex files.

I have seen a lot of .odex files below the path /system on my phone. I am just curious if there are also .odex files for my installed apps.

I searched the file system but I wasn't able to find .odex files for my installed apps. But I assume that they exist - the question is just where they are stored.

BTW: My phone is a rooted Samsung Galaxy Nexus with Android 4.1.2

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I think only prepackaged system apps will have .odex files because any other app isn't optimized specifically for your device, although I could be wrong on that. – Matthew Read Oct 29 '12 at 20:17
up vote 1 down vote accepted

When your ROM is booted up for the first time, Android's Dalvik goes through every apk and extracts the dex file from it. It places the dex files in the cache folder - located at /data/dalvik-cache. This is the directory that gets cleared when you clear the dalvik cache in your recovery tool

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So Android generates odex files in /data/dalvik-cache only the first time you boot Android? Or the odex files are generated every boot if the cache is empty? – kinunt Feb 9 '15 at 18:16

I believe every app has an ODEX db because this keeps the app files for running the app,the widget or apk cant work without it. Its normally located in the Secure file system under apps,each app with have its icon and the odex file with the same name .ODEX next to it.

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