the mobile version of QQ security center APP can view the devices that log in to the city and online.
2."tencent/mpbileQQ "or" tencent "is available. It is often used, that is, there are many files in the account, so you won't ask someone who added your QQ.
3. There is a drop-down menu next to the account. Click it and then select the account you want to delete (don't click to select the account at this time, just move the mouse over). There is an "X" next to the account. Click X to pop up a dialog box, and you can delete it according to what you want.