1.Yes. And 2. I think so. I've never used it myself.. but I've heard it works great. Mobile Odin. Found on playstore. I still advise against it.. flashing anything comes with a risk.. that said. Flashing from the device... hmmm.. truthfully.. I don't think it's possible.. you would be replacing the system files from the system... no.. I would not risk that.. lol
*So far as the theories of mathematics are about reality, they are not certain; so far as they are certain, they are not about reality.
*Do not worry about your difficulties in mathematics, I assure you that mine are greater. - Albert Einstein (1879-1955)