Hi ArcadioGarcia,
Take a look at the documentation from W3shcool:
http://www.w3schools.com/html/html5_webstorage.asp, the following words might be the reason that you cannot get [1,1,1,1] but a string, you need convert it before using.
Tip: Key/value pairs are always stored as strings. Remember to convert them to another format when needed.
By the way, the default way to do this in Windows Store App is to use WinJS.Application.local object
--James
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Thanks
MSDN Community Support
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