Secret Lab - Action Game for Cardboard VR

Hi guys, so I have been working on a Cardboard VR game in UE4. The premise of the game is to dodge lasers and energy shots, missiles and other obstacles. When you get to the end of a stage you get to fight a boss and destroy it. It’s available in alpha testing here:

Dodging lasers

A turret

Turrets and missiles

More turrets

A missile

A boss battle

I don’t exactly have an artist so the 3D models are pretty simple, and also performance is a big concern. On my Nexus 5X I find it difficult to maintain ~60fps for a long period of time.
I originally got the idea for the game when I thought about what type of game would suit VR the most and I was partially inspired by Jetpack Joyride and its simplicity, however as development went on the game veered towards dodging bullets and obstacles more. It’s my first time making a VR game so any feedback is welcome.