Where is hidden additional data of an app stored?

Question

This question came to my mind when I installed Oxford Dictionary. It's strange that I couldn't see the additional files (audio, dictionary, and pictures) in an unrooted device. This app has a base app (idk what it's called) and it will download the additional files through the app (these files are not automatically downloaded when the app's installed from playstore).

The reason I need to know the storage placement is, so I could copy the additional files and paste to let's say SD Card or OTG memory stick and ditto to my other device, so that I needn't download it again because the file is quite huge.

The problem is I couldn't find it anywhere. Is it because my phone is unrooted since it's probably stored in deep storage that requires root to modify it? If that so, at least, when I check the properties of the storage of the app i.e. that is placed in Android > data, (the name of folders are usually started by "com. xxx") the file size shows 0 kb that means nothing's there. At first, I assume it happens because my device is unrooted and I came across with this discussion here that I can actually see the root files (using MiXplorer), but I can't modify it. Well, even if I couldn't modify it, at least, I should be able to see them. However, I've searched the files everywhere and I still couldn't find them. What's the problem?

It says there that it's stored in internal storage and usually oxford products are saved in Android / data / package name

However, this is what I mean when the file size is 0 and there's nothing in there. I'm using MiXplorer btw and I've tried to check in root storage.

Anyway, Is it possible to find and copy the hidden additional files? Using app or maybe with the help of PC using certain software I can?

Does this answer your question? Where Android apps store data? — Irfan Latif, Feb 01 '22 at 23:02
@IrfanLatif unfortunately no. The discussion doesn't answer my problem as to why the listed package folder shows 0. — user516076, Feb 01 '22 at 23:53
Does this answer your question? Transfer Android app with offline data to NEW PHONE without ROOT — alecxs, Feb 02 '22 at 00:11
Does this answer your question? How do you extract an App's data from a full backup made through "adb backup"? — alecxs, Feb 02 '22 at 00:16
@user516076 please read my answer completely including the comments. — Irfan Latif, Feb 02 '22 at 03:52
Sorry guys. But I think you've misunderstood my question. I don't need to backup nor I still couldn't find the reason whythe size shows 0. But thanks for your attempts trying to help me. I've even clicked all those blue links from the answer and the comment and there is no a sentence explaining as to the problem I'm having. I only need to copy the file without backing up and do complicated things. — user516076, Feb 02 '22 at 07:30
@user516076 I think you misunderstood the other posts. You don't need root to modify the app data in internal storage (/data/data respectively /data/user/) you need root to see those files! No root no access to those files. If both phones are running Android 11+ then may be the Android device migration wizard is able to migrate these data when connecting old and new device via USB but that is just an unconfirmed theory (did not had this case in reality). — Robert, Feb 02 '22 at 08:12
@Robert no sir. I mean. I can't modify the file that's probably stored in root/deep storage/system/whatever idk the name. — user516076, Feb 02 '22 at 08:17
Use adb from a PC connected via USB to the phone. Check if you can copy the files. As a user on an unrooted device adb gives you the highest permission you can reach for reading and writing files. — Robert, Feb 02 '22 at 08:26

score 1 · Accepted Answer · answered Feb 02 '22 at 11:39

Is it possible to find and copy the hidden additional files? Using app or maybe with the help of PC using certain software I can?

yes, if your device has previously unlocked bootloader and Magisk installed, you can read/check size of

/data/user/0/com.oup.elt.dicts.bilingual/files

otherwise connect your phone via adb, create backup and extract it (see linked questions)

adb backup com.oup.elt.dicts.bilingual

Where is hidden additional data of an app stored?

1 Answers1