Recently I have a bug in Lightroom mobile version app. That is , A image before exporting in Lightroom looks different and after exporting it the image looks totally different. I am linking the images below for reference please do check it out and help me out with this problem. ( The first one is the image from Lightroom before exporting. The second one will be the image after exporting)
How did you export and what color profile did you use? Differences like this are almost always caused by (lack of) color management issues. If you exported in AdobeRGB for example, and then view the image in an app that does not know color management (very likely on a mobile device) then you will indeed see the wrong colors.
Even sRGB does not guarantee the same colors in different apps.
I'm sorry, that's all I can say. There are no guarantees on non-color managed devices like phones. Each app may interpretate colors differently
Yes, any image on the web should be in sRGB.