Avoid rerendering child when passing object in props

As other answers said, you need to pass a function as a second parameter to React.memo that will receive the previous prop and the current prop so you can decide if the component should be rerendered or not (just like shouldComponentUpdate lifecycle for class components).

Because comparing an entire object to see if anything changed can be a expensive operation (depending on the object) and because you can have multiple properties, one way to make sure it's efficient is to use lodash _.isEqual.

import { isEqual } from 'lodash'

const PerformanceComponent = ({style}) => {
     return <View style={style}>...</View>
}

export default React.memo(PerformanceComponent, isEqual)

This way you don't have to worry about implementing the isEqual and it also have a good performance.