I want to create multilingual app in Windows Phone 7. I am doing it from the help of one example but it is not giving me perfect solution. This is the link.
This link gives you a good description on how to go about it. Also, check the best practices.
For my own app i used this guide. Goodluck!
After following that guide, you can use your localized strings in a listpicker (as requested in your comment):
<toolkit:ListPicker.Items>
<ListBoxItem Content="{Binding Path=AppResources.ListPickerOption1, Source={StaticResource LocalizedStrings}}" />
<ListBoxItem Content="{Binding Path=AppResources.ListPickerOption2, Source={StaticResource LocalizedStrings}}" />
<ListBoxItem Content="{Binding Path=AppResources.ListPickerOption3, Source={StaticResource LocalizedStrings}}" />
</toolkit:ListPicker.Items>