Where are app files on android

Where does Android store apps on my device?

Android typically stores installed apps (.APK files) in the following directory:

Apps in these directories use a naming convention according to the unique package name, which is specified by the app developer. For example, if an app’s package name is com.example.MyApp , then the app is stored in the following directory:

Unless you have a rooted (or «jailbroken») device, you cannot see the contents of this directory and it will appear to be empty. This is because Android does not allow access to this location within the file system. Android uses the /​data/​app/​ directory for managing app data, and any tampering with files in this location could cause problems. Below is a sample screenshot of the /​data/​app/​ directory on a device with root access:

If you’re wondering what the «.odex» files are, they are files that Android creates to optimize the boot loading process for your apps. You can read more about this file type on the .ODEX file extension page.

While /​data/​app/​ is the most common location for installed apps, there also other directories that are used for storing apps. Different apps may by installed in different locations. Here are some other possible directories for installed apps:

• /​system/​app/​ — Contains pre-installed system apps
• /​data/​asec/​ — Stores secure apps generated from external memory storage
• /​data/​app-private — Contains third party protected apps

Apps may also generate data for use during runtime. For example, an app may create a database file that stores favorites or recently viewed items. The data for these apps can be stored in the following directories:

• /​data/​data/​
• /​mnt/​sdcard/​Android/​data/​

These directories also use the Android package naming convention. For example, /​data/​data/​com.example.MyApp is the location for the data stored by MyApp.

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Where does Android store apps on my device?

Android typically stores installed apps (.APK files) in the following directory:

Apps in these directories use a naming convention according to the unique package name, which is specified by the app developer. For example, if an app’s package name is com.example.MyApp , then the app is stored in the following directory:

Unless you have a rooted (or «jailbroken») device, you cannot see the contents of this directory and it will appear to be empty. This is because Android does not allow access to this location within the file system. Android uses the /​data/​app/​ directory for managing app data, and any tampering with files in this location could cause problems. Below is a sample screenshot of the /​data/​app/​ directory on a device with root access:

If you’re wondering what the «.odex» files are, they are files that Android creates to optimize the boot loading process for your apps. You can read more about this file type on the .ODEX file extension page.

While /​data/​app/​ is the most common location for installed apps, there also other directories that are used for storing apps. Different apps may by installed in different locations. Here are some other possible directories for installed apps:

• /​system/​app/​ — Contains pre-installed system apps
• /​data/​asec/​ — Stores secure apps generated from external memory storage
• /​data/​app-private — Contains third party protected apps

Apps may also generate data for use during runtime. For example, an app may create a database file that stores favorites or recently viewed items. The data for these apps can be stored in the following directories:

• /​data/​data/​
• /​mnt/​sdcard/​Android/​data/​

These directories also use the Android package naming convention. For example, /​data/​data/​com.example.MyApp is the location for the data stored by MyApp.

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How to Find Downloaded Files on Any Android Device

Finding the downloaded files on your Android device is usually an easy task. The steps to finding them vary slightly, depending on what kind of device you have, but for some reason, the downloaded files tend to “disappear” sometimes.

The files haven’t disappeared, though. You just have to dig in to your Android device’s settings to find them. In some cases, you may need to install a file manager to help you keep those downloaded files under control. Let’s take a look at some options.

Also read: 10 Best Sticker Packs for WhatsApp

Look in the Downloads folder

Like most computer, Android does come with a “Downloads” folder to store all your downloaded files. This won’t usually be available as an app unfortunately, but as a folder within a file manager.

You can find the Downloads folder using a third-party file manager, but each Android phone also has its stock file manager app that you can equally well use.

On stock Android, this app is just called “Files.” Simply open it then tap “Downloads” to access the Downloads folder.

Your downloaded files should be listed, with the most recent one at the top. If you tap the three-dotted menu option at the top right, you can do more with your downloaded files – you can clear your download history, edit, share, and sort by.

To make your downloads easier to find, you can use the “Sort by” option and organize them either by time, type, name, size, ascending or descending – whatever works best for you.

Alternatively, you can select individual files in your downloads list by tapping the three-dot menu icons next to them, which will bring up various options like Delete, Share, Rename and so on.

If you want to bulk-select or bulk-delete files in your downloads, long-tap one of the files until the checkboxes appear, then tap each subsequent file you want to carry out the same action for.

Check Your App Settings

Many apps have their own download settings. Instead of sending your Android downloads to your device’s download folder by default, they’re sent to the app’s download folder.

Case in point: WhatsApp by default downloads images and videos to your phone and keeps them in its own folder. In the “Files” app, this is separated into WhatsApp Images and WhatsApp Videos.

If you’re using a third-party file explorer, you’ll find the WhatsApp downloads in Internal Memory/WhatsApp/Media.

You can also check within your app’s settings. You may be able to change where files are downloaded by default to keep everything more organized on your device.

Use a Third-Party File Explorer

While the built-in file manager works well enough in Android, it’s not perfect. If you can’t find what you’re looking for, try a third-party file explorer app. There are a variety of Android file managers to use. However, a highly popular and useful option is X-plore File Manager. The dual-pane feature makes it a personal favorite.

It’s easy to use. The menu on the right includes a Find feature. You don’t need to know the full file name. I also love that search tips are included in the search box. Enter part of your file name and locate your file in seconds.

Download Another File

If you can’t find your Android downloads now, why would you download something else? When you download a file, you get a notification in your device’s notification tray. The notification looks like a checkmark.

Tap it and you’re sent to the downloaded file, meaning you can also check out where the download came from. This is an easy way to see where your downloads are stored by default.

How to Find the Downloads Folder from Your Windows Computer

If you just can’t stand how small things look on your Android device, you can always look at your downloads on your computer. Connect your Android device to your computer with a USB cable, and within a few seconds, you should see a prompt appear offering to show you the contents of the device you connected.

The next window will offer various options such as import/export (among others). Click on the one that allows you to see the contents of your Android device. Click on the Phone option and scroll down until you find the Downloads folder. Just open it and do whatever you please.

Also read: How to Share Files Between Android and Windows on Your Network

Find Your Downloads in Chrome

You downloaded an image last week but accidentally erased it from your device. To recover that image, open Chrome, tap the three-dotted menu icon at the top right corner, then tap Downloads to see your list of downloads from the browser.

If you want to find a specific file such as video, tap on the drop-down menu beside Downloads and tap on videos (or whatever file you’re looking for).

Also read: 10 New iOS and Android Mobile Games to Play this Month

Find Your Downloads in Edge

The new and much-improved Microsoft Edge browser is slowly making inroads on Android, and makes it relatively easy to find your downloads.

Open Edge, then tap the three horizontal dots at the bottom-centre of the browser and tap “Downloads.”

That’s it. All your downloads should now be visible to manage.

Find your Firefox Downloads

Firefox makes it just as easy to find your downloads. Once you have the browser open, tap on the three vertical dots at the top-right (or bottom-right, depending on your personal setup) of your display.

After that, tap “Downloads”, and you’re good to go.

As you can see, your downloaded files didn’t disappear, they just went to a folder created especially for that. To dig a little deeper still into your Android directories, you should read our guide on how to install TWRP Recovery. Or if you’ve started dabbling in streaming movies and TV between your devices, see our list of the best DLNA streaming apps.

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Crystal Crowder has spent over 15 years working in the tech industry, first as an IT technician and then as a writer. She works to help teach others how to get the most from their devices, systems, and apps. She stays on top of the latest trends and is always finding solutions to common tech problems.

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How to Correctly Store App-Specific Files in Android

Christophe Versieux (Waza_be) posted a rant about android developers’ bad habit to store files directly on the root of the sd card. I completely agree with the post. It’s bad usage to create app-specific folders directly at the root. If you install a lot of apps, the sd card’s root gets cluttered fast.

One comment also mentioned that most tutorials do not cover the app-specific folders, so let me correct that with a short tutorial on how to do it correctly.

App-specific files vs. app-independent files

If you need to store files there are generally two usage types:

• App independent data
• App specific data

I will cover both types in more detail in the following sections. But in short I would characterize those types as follows: App-specific files are those that only are useful for as long as the app is installed (e.g. ebooks in a proprietary format). App-independent files on the other hand are those that the user cares about regardless of the specific app that created them (e.g. photos).

App-independent files

This type of data is stuff your user very likely cares about, even if your app is no longer installed on the device. Examples are photos shot, images processed or sketched, code-files edited, audio files bought and so on.

For most of these types, Android provides special directories. A full list of directories that Android provides out of the box can be seen in the documentation of the Environment class. Those fields all start with «DIRECTORY». E.g. DIRECTORY_MUSIC or DIRECTORY_PICTURES.

Those files always have to be stored on the sd card (or the equivalent partition for devices that have no sd card slot like the Google Nexus line). The reason is, that those files tend to be quite large, that they need to be world-readable and that they must not be stored in a directory that get’s cleaned up when your app gets uninstalled. I will cover external storage in more detail in the following sections.

You can get access to the root of the sd card by calling the getExternalStorageDirectory() method on the Environment class.

And you can use getExternalStoragePublicDirectory(String type) to directly get a File object for any of the supported types:

It’s the usual Java IO API from here on.

App-specific files

This type of files is for any kind of data that only this specific app can or should make use of. This could be proprietary files like ebooks, media files that should not be available through the normal media players (e.g. thumbnails for CD covers), downloaded magazines, database files, preferences and so on.

App-specific files can be stored internally or externally (on the sd card) and the Android API helps you to find the appropriate directories.

What’s nice for app-specific folders that follow a certain naming convention is Android’s cleanup mechanism. Android takes care to delete these folder when users uninstall your app. This way Android gets rid of unnecessary files and users do not have to clean up manually after any deinstallation.

Internal storage versus external storage

You should know that there are two app-specific folders for any app. The internal one which you can use for private files and the external one. External storage refers to the sd card of Android devices or the equivalent partition that devices with no sd card option offer (e.g. the Nexus line).

Internal storage space can be limited

Especially for larger files you should prefer the external storage option. You should do so because internal storage space can be very limited depending on the device of your user. A probably extreme example is my old LG Optimus One that has only about 300 MB of internal storage. But with a 16 GB sd card I have plenty of external storage. Even if this device is one of the worst examples regarding internal storage, there are plenty of devices out there that also come with little internal storage. Not everyone uses high-end phones.

Permissions for writing to external storage

Whenever you want to access files on the external storage you need permissions to do so. Add this permissions to your manifest file:

The need to declare this permissions is a slight drawback compared to internal storage. Some users may be wary — especially if this adds to an already long list of permissions. But if you explain this in your app description you should be fine.

Note: For reading files of the sd card no permissions were needed prior to Jelly Bean. So you can leave this one out if your build target is lower than API level 16.

External storage might be unavailable

The biggest problem with external storage is, that it might be unmounted when you need it. That’s obviously the case when the sd card is ejected but also when your device is mounted for file access to your computer. Because of this, you always have to check, if the external storage is currently available:

Sometimes the external storage might be mounted read-only. If you only need to read data the following check is better suited for you:

This works since the value of the final field Environment.MEDIA_MOUNTED_READ_ONLY is «mounted_ro» . I actually do not like code, that uses knowledge of final fields’ value. In my opinion it would have been better, had Google chosen to use an integer so that we could use final fields as bitmasks to test for the state.

Internal app-specific directories

Android creates a directory private to your app for you. Your shared preferences go in here, as well as your SQLite databases, native libraries or cached files.

All app-specific files are within a folder named

Within this folder some common sub-folders might exist — depending on what your app needs:

• databases — for SQLite databases
• shared_prefs — for your preferences
• cache — for cache files and data
• lib — for native libraries
• files — for files that do not fit into other categories

The Context class provides some methods you can use to create new directories, open InputStreams and so on. The following table lists these methods:

Methods to help you with internal storage

Method	When to use
deleteFile(String name)	Deletes the file with the given name
fileList()	Returns a list of files
getDir(String name, int mode)	Returns a file object to this directory. If the directory doesn’t exist yet, it gets created.
getFilesDir()	Returns a File object pointing to the files directory
openFileInput(String name)	Opens an InputStream object to the file with the given name
openFileOutput(String name, int mode)	Opens an OutputStream object to the file with the given name. The file gets created if it does not exists

Some methods use a mode parameter. This can be any of the following constants of the Context class:

• MODE_APPEND
• MODE_PRIVATE
• MODE_WORLD_READABLE
• MODE_WORLD_WRITEABLE

These are int values and you can use the or operator («|») to combine them — e.g. to append to a world readable file:

External app-specific directories

This is where Waza_be’s rant comes into play — because too many apps ignore the correct handling of app-specific directories on external storage.

All external app-specific files should be stored within a folder named

Note that I use a relative path. This path is relative to the root of the sdcard. The convention of where sdcards are mounted, changed between Android releases.

It’s always good practice to use API calls instead of hard-coded values, but the fact that the mount-point has changed in the past should make you even more cautious.

Now for external files there exists only one method you can use:

If you pass in a null value the File object will point to the files directory. If you add any of the directory constants of the Environment class, you will get a File object pointing to a sub-directory within your files directory. If the directory doesn’t exits yet, Android creates it for you. If the external media is not mounted, the method returns null.

Note: This method has only been introduced with API Level 8 (that is Froyo or Android 2.2). In the next section I briefly touch on the issues you face when dealing with older devices.

Older devices

There are still devices out there on older versions, which you might want to support. In this case using the naming convention shown above is still a good idea.

Alas, neither the method getExternalFilesDir(String type) exists, nor does Android clean up after an app uninstall. But using the same naming convention still avoids too many irritating folders on the root of your sd card.

Cache

Many times you need to cache data you downloaded from the net or created within your app. Android allows you to use internal as well as external storage space to use the cache. But using the external storage can be risky, since your cache might be unavailable when you need it.

The Context object has two methods to get a File object for either the internal or the external cache directory:

You have to take care of the cache size yourself. Android deletes all files in both directories on an uninstallation of your app, but otherwise it’s up to you to clean up any cache files no longer needed.

If Android is running low on internal storage it cleans up cache files first but the API states explicitly that you should not rely on Android to clean up for you!

With the external cache storage Android doesn’t care at all. Even if the external storage is full, no cache files will be deleted.

Naming of the folder

The official naming convention for the folder contains your package name. Christophe Versieux (Waza_be) himself mentioned that he used to use the app name instead, since users are more familiar with the package name of the app.

Even though familiarity is something to consider, I do not agree with this statement. First of all the API call uses the package name, so why not use it. Only with this method you can rely to be on the safe side. Secondly Android only cleans up a folder using the package name. And finally you could get screwed since app names do not have to be unique. In this case you might end up doing stuff in your folder that clashes with the intentions of the other app.

Be aware of the «.nomedia»-switch

Android’s MediaScanner regularly scans the sd card for any media files and adds these to the public list of media files. Thus images will show up in the Gallery app or music files in audio players.

But that’s not always what you want. Sometimes those files really should be presented by your app only. That’s where «.nomedia» comes into play. If a folder contains a file named «.nomedia» it will be skipped by the MediaScanner and any media files will thus not show up in the public media list.

That’s another reason to use the standard app-specific folder. It contains the file «.nomedia» within the data directory so that any media files you add to your app-specific directory will not show up.

Lessons learned

In this tutorial you have heard about the difference between app-specific and app-independent files and how to apply this knowledge to Android.

Also you have seen how to use app-specific files on Android, and how to leverage the internal storage as well as the external storage.

In a follow up post I will cover how to add app-independent media files to the corresponding content providers, so that they show up immediately in the list of public media files. Stay tuned.

Edited:
Minor changes due to comments by +Alexandre Roman and +Cyril Mottier to my G+ announcement of this post.

Wolfram Rittmeyer lives in Germany and has been developing with Java for many years.

He has been interested in Android for quite a while and has been blogging about all kind of topics around Android.

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