When using a property with the type of number, it's not possible to use percentage-based values.

var styles = StyleSheet.create({
  myStyle: {
    position: 'absolute',
    width: '100%' // throws an error
  }
});

It would be nice to support this, so you don't have to calculate the value to px yourself. Using a string would also allow other units to be used — If using number type, it would still be px-based value.

This would also make it easy to make things responsive.