Are you taking class with her since you're asking for her? Then I'd recommend you buy yourself a phone for the US and she buys herself a phone for the UK. Since you seem to care a lot for each other you can - when needed - swap phones as necessary.
Man, if she's your daughter and she goes overseas let her take care for herself. If this post is not totally embarrassing for her I tell you it is.
Are you taking class with her since you're asking for her? Then I'd recommend you buy yourself a phone for the US and she buys herself a phone for the UK. Since you seem to care a lot for each other you can - when needed - swap phones as necessary. Man, if she's your daughter and she goes overseas let her take care for herself. If this post is not totally embarrassing for her I tell you it is.