Checking Last Activity
There are two ways to check for your recent activity in Google.
List of Devices Recently Used
The first one is to check the list of devices recently used, it is incomplete but a good start. Go to this page : https://myaccount.google.com/device-activity
You can see here all the devices used recently :
If you click on any device, you can see the last activity and the software used. For other devices than the one you are using, you can disconnect them:
It is interesting but not showing detailed information of where the connection is coming from, only an attempt to geolocate the city.
Checking Last Account Activity
The get more in depth information, you need to go on your Inbox and click on "Details" at the complete bottom right of the page :
This page gives detailed information on your recent activity, including the IP address and the browser User Agent (if you click on "Show Details"):
This information is only available for a short period (a couple of days or weeks), so if you see any sign of suspicious activity, please take a screenshot or write somewhere any interesting information (date and time, IP address, user agent) as it may not be available next time you will check this page.