How do I download apps to my SD card on zte obsidian

[Griffin78052]

I've been trying to download hearthstone but when I opened the app I did not have enough storage to play it so I bought an SD card for my zte obsidian and I don't know how to download apps to it.please help

 

[Griffin78052]

No it still doesn't work.it says that my phone storage and internal SD card are the same.