There you have it, a simple gesture steering experience for the Google Cardboard! If you enjoyed this series, there are quite a few ways to continue working on this project and improving it. Some good places to start are:
Create a lose game state (Display some type of message that the user has lost or some change in visuals)
Create a win game state (Display some type of message that the user has collected all the coins)
Add a visual indicator (like the scene having a red tint) to communicate to the player that a shark is stalking the main character, even if the shark is currently not visible.
Add in more sea creature NPCs (friendly or otherwise)
Improve camera-dynamic object collision, to create a more precise interaction between the shark(or other objects you choose to add) and the main camera/GvrMain
Deactivate the active coin and arrow when the player dies.
If you have any questions, complaints or would like us to do an extension of this tutorial based around gameplay, feel free to email us at firstname.lastname@example.org . We value your feedback!
Shark Model: https://www.cgtrader.com/free-3d-models/animals/fish-aquatic/silvertip-reef-shark
Sea Floor Assets: http://docs.unity3d.com/Manual/HOWTO-Water.html
Inspiration for Underwater Script: http://wiki.unity3d.com/index.php?title=Underwater_Script