Jio Phone 2 does have the 4GB internal memory. Practically, it has unlimited contact book.
Yes, Jio Phone 2 does have the support for the Kannada language.
Yes, Jio Phone 2 does have the speed dial.
No. You cannot use the 3G network on Jio Phone 2. You can use the 4G network and 2G network.
No. You can use Instagram website but you cannot use the Instagram App on Jio Phone 2.