Although Microsoft said that WP7 application porting to Win8 above is relatively simple, only need to modify some of the API and design in principle the details, but also provides a relatively concise reference document;
In fact, this kind of migration is still a lot of work, especially when the application refers to more underlying APIs.
Here are a few issues to consider in porting your application:
(1) UI: Basically all of the UI page will be changed, mainly a reference library changes, some wp7 on the win8 above the control is not supported, such as PhoneApplicationPage.
(2) Database: Currently WIN8 no source database, but can use SQLite to achieve data storage; Win8 also does not support sqlce databases in WP7.
(There are still system.data.linq such Win32 libraries in WIN8, which can only be faulted if the 64-bit environment compiles)
(3) If the original WP7 application also involves registering a mobile phone alarm clock, but also have to reconsider the logic of the bell. There is no concept of a clock in win8, but consider switching to a supported message push notification (i.e. implementing timed push notifications, referring to blogs).
(4) Background process model: WIN8 background model and WP7 similar, background process cannot run continuously (interval run once), can refer to: Blog or MSDN document.
(5) Other changes to the reference library. For the time being, we have not found a complete reference document, only scattered search and replace.
We have to spit out a bit. NET libraries, a DLL library will have n multiple versions, accidentally will be wrong ... It's a catastrophe to use such a library.
WINDOWS8 development-about WP7 app migration to WIN8 Metro style