show 2 items per row[react native]

The correct way to do it would be with flexBasis, with a value set to (1/n)% where n is the desired # of rows > 0. For two rows:

.parent {
    flex: 1,
    flexWrap: 'wrap',
    flexDirection: 'row'
}
.child {
    flexBasis: '50%'
}