Is there any way to transfer apps directly from a different device? I have a very good dictionary app I purchased on Google Play several years ago. It’s not available for download any more, because the publishing house doesn’t sell digital dictionaries any more, instead you must pay a yearly subscription.
However, I have been able to transfer the app to new Samsung devices using their Smart Switch app. Is something similar possible on eOS?
You can transfer the .apk via ADB, but depending on where your “license” is stored, this might need additional files, if the .apk itself isn’t in itself a “full version” package.
There are various backup tools, as well - those can backup the applications either directly to (a) file(s) or to a cloud service / vault. It is important that you have a possibility to restore the backup on your other phone, which depends on the tool and its way of saving the data (some prevent one from playing the backup back to another device).
Edit: Depending on the way you choose, you might need root access.
Depending on what version of e/OS/ you have, you could use SeedVault.
Can’t find the guide how you can copy and paste it to here
A German tutorial (could be translated via webservices easily) is here:
Not especially for /e/, but the basics seem compatible.
But I’m not used to “only” backing one application up with it.
For such a task I partly use the adb pull command.
There’s some information in this regarding SeedVault usage:
But regarding a tutorial for copy & paste I’ve not found anything specifically as well.
Not every e/OS/ version has the same SeedVault version.
Proper appdata is only available from a13 (T).
The copy paste was about Android version from the System settings.
Ah, that clears the misunderstanding. 
Thanks! I don’t want to root my Samsung phone and I’ve never used ADB either, but maybe it’s not too complicated? How should I go about finding and transferring the necessary files for just this one app? I really don’t want to lose it, because it is not obtainable any more, but neither do I want to be locked in in the Samsung universe.
Is that phone where the dictionary app is installed a Samsung with stock ROM?
Yes. One UI 7.0, Android 15. But the dictionary app was originally on a Pixel phone, I think I bought the app around 2018 or even earlier. I discovered that it had disappeared from Google Play a couple of years later, when I swapped phones. But I could transfer it with the Samsung Smart Switch.
Hmm, it depends on ones knowledge of the command line interface and the necessities of it, like: correctly written commands, no mistakes regarding folders, else you can ruin a lot - or end with a backup which you don’t find.
The application itself has a specific name, called the application ID, you can find that one under Settings => Applications (or Apps) => Show all apps => Find the app you search for and click on it.
On the lower edge of the screen if you scroll down you’ll find its version number and below the package application ID.
That’s the first step to know how the application itself can be identified, in places where it is not listed with its name (like as an .apk in the folder structure).
For adb usage, there are several necessities, like unlocking the developer mode in Android itself, activating the adb USB accessibility etc. - not to talk about setting up the adb tools on your computer. That’s somewhat more complicated, depending on what you have in experience out of a technical view.
A backup application might be ways more comfortable and less hassle in your case. Regarding the Samsung phone I’ve no idea how well those work with One UI 7.0 and its “vendor limitations”, unfortunately.
“Neo Backup” could eventually be an option for both of your devices (or OS’es), as it allows a quite easy backup of applications and (some) user data. But it seems to still need su / root rights.
@K4096K wrote an article about hardening an /e/ OS towards safe and secure usage by kids (or other users) with limited access to settings and functions. He / she explained the way of removing pre-installed applications by adb in a part of the article, which as well shows how to pull an .apk over:
https://medium.com/@k4096k/a-safe-android-for-kids-eb9f63973312
But it is still more hassle than to “click some buttons in a GUI”, you see.
Getting something like that into /e/OS will not be easy. Root and some adb will be needed as far as I can tell. I have no knowledge about that, good luck.
You might try AntiSplit-M. Some apps store themselves under a split APK. To extract a split APK for installation on another phone you have to extract it then merge it. Not many APK extractors can merge split APKs. Of course if it’s not split, there’s lots of APK extractors that will work.
You don’t need ADB for this, you just extract the APK with the app, copy it over, then open in it in the Files app to install it. I don’t know how Smart Switch handles transferring apps, but normally when you install an app its APK is stored in the system volume. If Smart Switch does something different an extractor may not work. If there’s a problem and you still have the phone where you originally installed the app, you could try it there.
Or you use something like SAI to extract as well as install it.
Thanks a lot! I’ll test as soon as I get my new old phone…
SAI has not been updated for 4 years so that’s why I recommend AntiSplit-M. It’s active with an updated release a couple months ago. I mean if SAI works then great, I know people still use it. But with no update after three major versions of Android there’s potential for problems.
But these apps don’t transfer app data? That might also be needed