How can I download sir in use...?
It is not something you download. It comes installed on all the current iPad Minis, iPad 4 and iPad Air.
Setup Siri (iPad 3 and later)
2. Language>English (United Kingdom)
3. My Info>Use default
5. Settings>Privacy>Location Service>Siri>On
Siri is not avaible on the iPad 2.
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