Hi there!
You can 'disconnect' your number from iMessages to avoid people's texts from iPhones getting delayed or not reaching you by going to Apple's ID site and managing your number from there (remember, use the same Apple ID you had on your phone).
http://appleid.apple.com
Unfortunately, since iMessage is NOT SMS/MMS, I'm not sure you can export or back up conversations from it to another OS. I found this tutorial but it seems you need the iPhone with you (or a previous back up of it).
https://forums.androidcentral.com/e?...token=gwsyK8f3