Samsung's latest Tizen phone is getting a new software update in India. Given its low-end nature and the fact that it runs a young OS (which is the main reason it's not a great deal), none of us here at SamMobile use the Z3 regularly so we're not sure what the update brings. Surprisingly, the update we received has the firmware version Z300HDDU0BOL4 and is a 41.7 MB download, while the same update for the folks over at Tizen Experts is only 3.6 MB.
It's possible we missed an update in between and that Samsung has combined two updates into a single one for those who missed the last one, but in either case, an update is available for all Samsung Z3 owners in India. You can wait for the update's notification to show up, or force it to show up through the Settings » About device » Software update menu by hitting the Update now button.