Just a mini-service alert, the Windows Phone Store (for at least those in the US) are having some issues that are "intermittent". Sometimes we can't even view and app let alone download it, yet other times we can get through (error code 805a01f7).

Needless to say it is annoying but Microsoft is aware of the issue and actively working on it. Best bet is just to give it a few hours while they figure it out and hopefully it'll get fixed right quick.