You can use API of any Language like ( Node. js, Python, Java, PHP) as a backend and use flutter just to fetch the data. It is most effective approach for large applications! I recommend to use Firebase as Backend for small application and Node.
Read moreIs Python good as backend for flutter?
Yes you can use Python as a back end for a mobile app using flutter in the front end but you can’t directly connect to backed, you need to write APIs. Then from flutter, you need to connect to those APIs using the HTTP package.1 Mar 2020
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