i want to ask a question. i sign in to my gmail account and I got an information that i sign in to my gmail account from a mobile device, but i did not. i had never sign in to gmail from a mobile device. but the IP was the same as all my other previous sessions. i just did not had the details ability on that particular sign in. can you tell me what is all about? my gmail.com account was hacked?
If you have signed in from a computer you don't normally use to check your mail you will get that notice.
How it works is Gmail is recording the devices Mac address and other device information, saving it to your account database and every time you log in it checks that information. If they are different then it sends you that notice.
So let's say you never check your mail from your work computer. But one day you do. You will get that message.