What are the differences between Flexbox in browser and Flexbox in React Native?

CSS Flexbox is used to design a responsive layout easily without using float or position CSS property. Float and position values were used to build any type of UI which are not very easy. Flexbox is added in CSS3. Flexbox is designed to provide a consistent layout on different screen sizes. You will normally use a combination of flexDirection, alignItems, and justify-content to achieve the right layout. 

There are few differences in default values of few flex based CSS properties between React Native and on the browser. The default value of flexDirection is a row in the web but in case of React native, its default value is a column. Also, flex parameter only supports a single number in React native. Flexbox alignItems has few more values like flex-start which start aligning element from start and opposite of this is flex-end which places the first child element at the end. Similar to alignItems, justifyContents also have values which behaves where much similar to flexbox behaviour in a web browser.