Follow The Few Steps To install Apps Directly To SD Card From Play Store.
For That First Open The "Settings"
And Then Scroll Down Click on "About Phone"
Click on "Software Information" to continue.
Then 7 Times Click on "Build Number" to Enable Developer Options. And go to Back.
Scroll Down And Click on "Developer Options"
Again Scroll Down And Enable 'Force allow apps on external"
If You Want To Hide Your Photos Then Click on Below Button.