Hello, could anyone explain me what are subaddresses, please?
In order not to confuse you with complicated tech stuff I ll give you a general description.
Subaddresses is like an one-off, disposable address you can create with your wallet (some people might object with the word disposable but that's the easiest word to use) which is different from your main wallet receiving address and offer it to the person that is going to send you Sumokoins.
You can give this person a different sub address each time, created by you, and all his payments will appear on your wallet without ever disclosing your main receiving address