What happens with app data when i delete an app

Specifically in the case of the Twitch app and Gmail I believe there is persistence across apps which is related to Safari and the cookies the browser stores. It appears that this will automatically serve up information to apps about your email address and login IDs to what I will loosely call "relevant apps". I guess this is something we all agreed to when we hit the "yes frock you just do it" button on one of the iOS updates, but yeah. Your information is automatically shared by Apple with whoever they see fit. (Their TOS literally says that they will share information with YOUR EMPLOYER if they see fit, regardless of how they would get that info.) I'd guess that you *might* be able to mitigate app cross-contamination by clearing your safari history but I'm not sure. Most Apple fanboys and paid trolls are going to tell you to reset your device and restore from iCloud, which is the Apple equivalent of "Do a System Restore".

Enjoy facts.

Yes, I understand what you mean. For those apps like Skype, Facebook, Google+, etc., of course all the data is linked to your accounts of their services. But for 'SoundHound', the case is different. Take a look at these:

I guess what 'SoundHound' does is that they let the user choose to store the app data up in the cloud. Now, let's say you have an iPhone and an iPad, and both use the same Apple ID and have installed 'SoundHound'. If you enable to use iCloud to save the tagged songs and bookmarks, no matter which device you use to tag the songs, the tag history and bookmarks will both appear on your iPhone and iPad (as you use the same Apple ID on both devices and the data is stored in the iCloud).

I haven't tried though, but I think it's the way it works. 😀

And the application data backed up to iTunes on Mac or PC (OR iCloud) can only be restored when doing a full restore on your iPod touch. Just ticking the app(s) you want to add back to your iPod touch in iTunes won't transfer the backed-up app data of the app(s) to your iPod touch. Doing so just means installing the apps. I've tried myself.

To the OP:

(talking on paper, I haven't tried myself but the logic is there)

There are some apps which let users choose whether the app data is stored in the device itself or into the iCloud. Just like the one you've mention, say 'SoundHound'. Let's say you choose to save the app data into the cloud, and you've used the app for a while (created some settings and so on). One day you decide to delete the app, and boom, the app is gone. But since the app data is stored in the cloud, if you want the app back, you just download and install the app, and (you may need to) fill in the information required for the app to get the data back from iCloud (for example, an Apple ID), and the app will be back to where you left off.

Hope it helps and correct me if I'm wrong. 😉

1. yes ofcourse you have to use that backup, not just reinstall the app. You are right about it restores all your things..

2. every app that stores in internet (like skype for example), will store it under your account and then when you install that app on whatever device it will load what is in your account. Not when you use iCloud syncing.

When you delete an app, the data is deleted also. BUT if you have a backup made (by sync to iTunes for example) from before the date of removal, the data are still there.