version 0.13.1 is very slow

I just update the library from 0.12.3 to 0.13.1 because of the propTypes warnings... Well, the warnings went away, but my app is now running extremely slow. Both in the simulator and my real phone. Especially the React Navigation.. the tabs are so slow to response. 

What caused the slowness?

I now went back to 0.12.3 and ignore the propTypes warnings....