Can I use my apple ID on my girlfriend's iTouch?

Essentially, I want to buy some apps on my AppleID and be able to install and play them on my girlfriend's iTouch.
Is this possible? If so:
What happens to her apps? Are they deleted (along with all of her highscore data etc) or will they simply be 'blacked out' and inaccessible?

Related to the above:
If I buy apps directly on the iTouch with my AppleID instead of hers, will I be able to put them onto another iOS device if I were to get one in the future? As in, will they be tied to my AppleID account rather than the system I bought them on?

As much information as you could provide would be really helpful.

She has a Generation 2 iTouch.

Cheers.

You can only use one Apple ID on an iOS device. Either choose to use hers or yours. If you choose to share your Apple ID on her iPod Touch, you would have to reset her iPod Touch to factory settings using iTunes and set it up using your Apple ID (that will remove whatever apps and songs she has on her iPod Touch). Whatever apps she purchased under her Apple ID can't be used on the iPod Touch if it is set up with your Apple ID. And vice versa.

When you purchase an app on your iPod Touch (for example), it can be used on up to 5 total iOS devices that are set up with your Apple ID. So yes, in the future when you get an iPhone (for example), those apps can be installed on that device as long as it is set up with your same Apple ID.

That didn't used to be true - I don't know if it's changed though. My first Apple product was an iPod touch - purchased while away from home (for father-in-law's funeral in Chicago). I bought iPod touches for both the wife and myself - and the brother-in-law - to get us up and running while we were out there - took them to his house and activated them and put a few free games on there using his iTunes account name and password. For the longest time (before I got an iPad - and everything else Apple that I have) I'd have to use his password to update those apps - along with my own password for the apps that were purchased from my account.

You can do it with apps just authorize your apple Id on her computer that u want on the iPod then download the apps u want when u sync add those apps. The only issue u will have is when u go to update them on the iPod it will ask her password for her apps and your password for your apps

RustProofCorn said:

You can do it with apps just authorize your apple Id on her computer that u want on the iPod then download the apps u want when u sync add those apps. The only issue u will have is when u go to update them on the iPod it will ask her password for her apps and your password for your apps

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Are you sure this works at the time of writing?
Have you done it recently with success?

I did it on my iPhone 3GS I now have a 4 and I haven't tried it. But yes I have done it I had 3 apple id's running on the 3GS because when I received the phone from my father some of the apps were his some were is wife and I added some of my own to the phone as well. When I added my own apps on the phone I went to settings then the app store and signed out of his account then signed into mine and just downloaded right to the phone without connecting to iTunes. Then when I synced to my computer I had to authorize my dads and his wife's account to be able to keep the apps that I wanted.

FYI I have not been able to do this with music or ringtones. If u try to do it with music it seems it deletes all the music off the iOS device.

RustProofCorn said:

I did it on my iPhone 3GS I now have a 4 and I haven't tried it. But yes I have done it I had 3 apple id's running on the 3GS because when I received the phone from my father some of the apps were his some were is wife and I added some of my own to the phone as well. When I added my own apps on the phone I went to settings then the app store and signed out of his account then signed into mine and just downloaded right to the phone without connecting to iTunes. Then when I synced to my computer I had to authorize my dads and his wife's account to be able to keep the apps that I wanted.

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I think the thing I'm most worried about right now is the highscores. Apple has a really strange way of screwing everyone over when it comes to using what you've bought on multiple devices, and I can deal with not being able to access my things on my girlfriend's iTouch, but I want to be assured that all of her data will remain secure if it doesn't work.

Pansworth said:

I think the thing I'm most worried about right now is the highscores. Apple has a really strange way of screwing everyone over when it comes to using what you've bought on multiple devices, and I can deal with not being able to access my things on my girlfriend's iTouch, but I want to be assured that all of her data will remain secure if it doesn't work.

Click to expand...

That is something I don't know about. If u don't remove any of here apps and then put them back on I doubt you will lose data but when doing this sometimes it's kinda confusing so if u hit the wrong button it can remove a app which u can put back on but would lose game saves. I would probably make a backup before trying what I mentioned.

RustProofCorn said:

That is something I don't know about. If u don't remove any of here apps and then put them back on I doubt you will lose data but when doing this sometimes it's kinda confusing so if u hit the wrong button it can remove a app which u can put back on but would lose game saves. I would probably make a backup before trying what I mentioned.

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How would I go about doing that? When I open the iTouch from My Computer it only shows the pictures folder.
I've enabled all hidden folder to be shown, but there's nothing there.

I'm sorry I'm not that great at explaining things. Not sure what part your confused about please let me know

Backing it up? If so open iTunes plug in your device and u will see it on the left. Right click on the device and u will see the back up option. This needs to be done on the computer she syncs with.

I was talking about the backing up. I forgot that Apple don't want us physically trawling our devices that we've paid for to back up folders and files ourselves.
It seems the only way to backup is via iTunes, and a few sources seem to think that it backs up save files and so on, so I guess that's as good as it's going to get without attempting to jailbreak it and possibly break it altogether (yeah, totally not going to do that xD)
Cheers for the advice, you've been more than helpful.

Np man hope it all works out