The Zenfone 3S Max is undoubtedly a one-trick pony. It has the biggest battery you can get in a device of this class that provides days of battery life without the actual device being massive in size.
Unfortunately, if you are a more demanding user there is not much else there to hold your attention. Battery aside, there isn't a lot to commend here, with the display and device performance being major weak points for this phone. Even the camera isn't really worth writing home about. And while it's good to finally see Android Nougat on an Asus phone, the ton of Asus bloatware on top spoils the experience a fair bit.
At 14,999 Indian Rupees ($222), the Zenfone 3S Max is also overpriced, considering you can get the fully loaded Xiaomi Redmi Note 4 and still have money to spare. The Xiaomi is also a better phone in every way and the battery life is on par, even though it has a smaller battery. This really puts the 3S Max in an awkward position where it's hard to recommend it as it really has no leg up on the competition in any regard.