Completely deleting an app and all data it stores on your iphone

[transphasic]

If I (stupidly) download a game from the app store, dislike it, I can then delete it by holding the icon down on the home screen and the icon will disappear. I always choose to "delete the app and all data" option.

BUT if I download that same app in the future, it is able to pick up from where I left off, showing that either my phone did not delete the background settings/info, or their servers retained it.

Is there a way to be certain of deleting all of the app's stored data and settings on my phone, beyond just deleting the app itself?

 

[Mr. Awesome]

If I (stupidly) download a game from the app store, dislike it, I can then delete it by holding the icon down on the home screen and the icon will disappear. I always choose to "delete the app and all data" option.

BUT if I download that same app in the future, it is able to pick up from where I left off, showing that either my phone did not delete the background settings/info, or their servers retained it.

Is there a way to be certain of deleting all of the app's stored data and settings on my phone, beyond just deleting the app itself?

It could be that the app in question is storing its data in iCloud. If that's the case, then before you delete it, go to iCloud settings and make sure the toggle for that app is switched off, then try again.

 

[transphasic]

It could be that the app in question is storing its data in iCloud. If that's the case, then before you delete it, go to iCloud settings and make sure the toggle for that app is switched off, then try again.

Good thought, but it wasn't listed in the apps there as "on". I think the developer can pull data from the phone like IMEI number, telephone number, etc., which of course it doesn't mention - or lists in tiny print in the usage agreement - and can then match it up if that iphone ever re-installs their garbage app.

No doubt, they'd promote it as being "more customer friendly" and "efficient" so that if a user loses/upgrades their phone, their game data will still be available.

I also noticed that in the app store, apps that were downloaded in the past, even if they were subsequently deleted, still have a cloud with down arrow icon, while other apps that i never downloaded have the "get" icon, so perhaps the data is being stored in the apple app store...?

 

[Mr. Awesome]

I also noticed that in the app store, apps that were downloaded in the past, even if they were subsequently deleted, still have a cloud with down arrow icon, while other apps that i never downloaded have the "get" icon, so perhaps the data is being stored in the apple app store...?

The cloud icon only reflects whether you've downloaded the app before and doesn't have anything to do with stored data.

 

[WarmWinterHat]

Apps can store data under the iCloud sync api. It's not user accessible.

 

[akash.nu]

Good thought, but it wasn't listed in the apps there as "on". I think the developer can pull data from the phone like IMEI number, telephone number, etc., which of course it doesn't mention - or lists in tiny print in the usage agreement - and can then match it up if that iphone ever re-installs their garbage app.

No doubt, they'd promote it as being "more customer friendly" and "efficient" so that if a user loses/upgrades their phone, their game data will still be available.

I also noticed that in the app store, apps that were downloaded in the past, even if they were subsequently deleted, still have a cloud with down arrow icon, while other apps that i never downloaded have the "get" icon, so perhaps the data is being stored in the apple app store...?

Without your consent no app can just get data on iOS such as phone number / IMEI etc.

Most likely it’s using iCloud to store progress data and when you install it that data becomes available to the app.

In any case when you uninstall an app on iOS be assured that no meaningful data stays physically on the device.

 

[transphasic]

Apps can store data under the iCloud sync api. It's not user accessible.

If not accessible, but can it be deleted?

 

[transphasic]

In any case when you uninstall an app on iOS be assured that no meaningful data stays physically on the device.

That is clearly not the case, as I deleted the app, then confirmed it was not using icloud or being stored in my backups - and then re-installed the app, and it put me back to where I was before I deleted it.

Try it for yourself, the two apps are "zynga poker" and "poker heat", both are pure garbage but both are clearly storing data for my phone somewhere, as the scenario I refer to happens with both.

 

[akash.nu]

That is clearly not the case, as I deleted the app, then confirmed it was not using icloud or being stored in my backups - and then re-installed the app, and it put me back to where I was before I deleted it.

Try it for yourself, the two apps are "zynga poker" and "poker heat", both are pure garbage but both are clearly storing data for my phone somewhere, as the scenario I refer to happens with both.

These apps might have the ad identifier aka UUID stored on their server for your device if you have not provided any personal information during your first usage. Apps can find out returning users that way.

 

[WarmWinterHat]

If not accessible, but can it be deleted?

Nope. You can dig out in the hidden iCloud directories on a a Mac and view it, but you can't do anything with it.

 

[transphasic]

These apps might have the ad identifier aka UUID stored on their server for your device if you have not provided any personal information during your first usage. Apps can find out returning users that way.

Correct, I "login" as a guest, providing zero information other than what it surreptitiously takes, as you mentioned UUID or other data.

Can the UUID be changed on a phone, like changing an IP address?

 

[akash.nu]

Correct, I "login" as a guest, providing zero information other than what it surreptitiously takes, as you mentioned UUID or other data.

Can the UUID be changed on a phone, like changing an IP address?

I think the only way for you to guarantee that the app will change the UUID is to reset the phone and setup as new.

It could be storing the UUID in the keychain which remains untouched even when the app gets uninstalled.

But just to emphasise, this is not your personal data.

 

[winxmac]

You would need to go the last screen of the iPhone/iPad (which is the app library for iOS 14/iPadOS 14 and newer) and delete the app which will also delete the data... If you press and hold the app and select the option remove the app, it just removes the icon from the home screen but not the app...

iOS 13/iPadOS 13 and earlier has the old way of the app gets deleted/uninstalled once removed from the home screen...

 

[kitKAC]

You would need to go the last screen of the iPhone/iPad (which is the app library for iOS 14/iPadOS 14 and newer) and delete the app which will also delete the data... If you press and hold the app and select the option remove the app, it just removes the icon from the home screen but not the app...

iOS 13/iPadOS 13 and earlier has the old way of the app gets deleted/uninstalled once removed from the home screen...

You can delete Apps and their Data from the Home screen, just choose the right option.

 

[klasma]

Apps don’t have access to the UDID (unique device identifier) anymore since iOS 6.

Apps who you give explicit permission to track can access the advertising identifier (IDFA), which is the same across all apps and thus allows to track your device across app vendors. You can enable/disable this under Settings > Privacy > Tracking and also see which apps are using it there. You can reset (change) the IDFA by first disabling and then re-enabling the tracking.

Apps also have access to a per-vendor identifier (IDFV) which is different between app vendors (developers) but specific to your device. The IDFV is automatically reset once all apps from the same vendor are deleted from the device. (So make sure you don’t have any more apps from the same vendor installed.) Access to the IDFV doesn’t require permission I believe.

Furthermore, apps can use the DeviceCheck framework to store two bits (binary digits) of information per device and app, which is persisted across app deletions. Two bits obviously aren’t enough to store any substantial app state, but they can for example be used to check if the app had been installed previously, or if some promotion has already been used.

Finally, apps can use various fingerprinting techniques that can enable them to recognize a previously fingerprinted device with a high likelihood (though not 100% certainty). This is disallowed by Apple, but difficult to prevent on the technical level. One extreme measure that can help here is iOS 16’s new Lockdown Mode. However, I would not expect a game app to use fingerprinting to restore game state, as that would be a dead giveaway that it does fingerprinting, which apps normally want to keep secret.

 

[transphasic]

You can delete Apps and their Data from the Home screen, just choose the right option.

That doesn't work, as my opening post explains.

 

[transphasic]

Apps don’t have access to the UDID (unique device identifier) anymore since iOS 6.

Apps who you give explicit permission to track can access the advertising identifier (IDFA), which is the same across all apps and thus allows to track your device across app vendors. You can enable/disable this under Settings > Privacy > Tracking and also see which apps are using it there. You can reset (change) the IDFA by first disabling and then re-enabling the tracking.

Apps also have access to a per-vendor identifier (IDFV) which is different between app vendors (developers) but specific to your device. The IDFV is automatically reset once all apps from the same vendor are deleted from the device. (So make sure you don’t have any more apps from the same vendor installed.) Access to the IDFV doesn’t require permission I believe.

Furthermore, apps can use the DeviceCheck framework to store two bits (binary digits) of information per device and app, which is persisted across app deletions. Two bits obviously aren’t enough to store any substantial app state, but they can for example be used to check if the app had been installed previously, or if some promotion has already been used.

Finally, apps can use various fingerprinting techniques that can enable them to recognize a previously fingerprinted device with a high likelihood (though not 100% certainty). This is disallowed by Apple, but difficult to prevent on the technical level. One extreme measure that can help here is iOS 16’s new Lockdown Mode. However, I would not expect a game app to use fingerprinting to restore game state, as that would be a dead giveaway that it does fingerprinting, which apps normally want to keep secret.

Good post, interesting info. I have the IDFA already set to "off" in the settings.

There must be some other identifier these apps/developers are using to use, perhaps the app store, just not sure but I will continue my research.