I'm using HSTS(Strict-Transport-Security Header) for web applications. As far as I know browser keeps that information and when a user tries to connect to my website, browser loads it via HTTPS directly. So MITM attacks are prevented.
I also have a mobile application which talks with a web api via HTTPS. Should I implement HSTS header for that? My opinion is it won't provide any additional security since there is no browser which keeps that HSTS header information for web api. Am I correct?