While Windows Insiders in India got Cortana on Windows 10 Mobile preview build a few days ago, the Fall Update for Windows 10 that released earlier today brings the Cortana experience to Windows 10 PCs in India officially (along with Japan, Australia, and Canada). You don't need to alter any Speech or Region settings to enable the functionality.
Members of the Windows Insider Program signed up to get updates in the Fast Ring who upgraded to the build 10586 a few days ago would've gotten the Cortana experience too.
As has been the case globally, the Cortana experience has been customized for the India market. I was notified about my pending Airtel bill and was prompted to pay it. The experience was powered by Paytm.
One of our readers, V Arvind Babu Nair, shared that Cortana interprets train booking via IRCTC. While the screenshots he sent are from Windows 10 Mobile, but it should be the same on your desktop.
Of course, you can always judge Cortana's localization by her irreverent humor. While she told me a joke with a Hindi reference, she also responded to a fun question on Diwali.
How do you like the Cortana experience on Windows 10 in India? Let us know of interesting scenarios of assistance she offers or the fun things you discover. Tell us in the comments!