XperiCheck has been around for a while now, and it’s proved to be a very handy website if you want to keep track of the latest firmware updates for your particular Sony Xperia device.
You can search through any Sony Xperia variant, which will list all of the current firmware versions available for it, including what is available across each region. It’s an easy way to see if your particular region of a particular firmware has been updated, without constantly connecting your phone to your desktop.
There is also a handy Twitter handle that provides a feed of all of the firmware updates as they are released by Sony. A number of you will already know of its existence, but if you don’t, it’s a site well worth bookmarking.