Well, Pokemon Go has the same game play that we have always found on Pokemon games before. You need to catch the Pokemons, fight it out in the gyms, evolve your Pokemons and collect rewards. Only difference with the Pokemon Go is - you do it in the real real world!.
That means you will actually walk to find your Pokemons. Gone are the days when you used your fingers to guide your avatar on the small screen of your device to catch the Pokemon and do all those tasks, you will need to do it in actuality.
How to play it?
To begin with, you will need to sign up either with your Google account or sign up for Pokémon Trainer Club account. Once done, customise your avatar by by specifying your color, gender, hair color and what not. Now, you will enter the Pokemon Map - your playing area. The map is an animated version of the Google Maps. You will see the landmarks as Pokestops or Pokemon gyms. As you walk, your avatar walks with you. Pokemon will pop up on the screen with vibration as you walk - if there is one. You just need to tap on it to capture it.
The game has many safety hazards associated with it. The reason is simple - you will need to walk around in the real world filled with cars, bikes and what not with yiur eyes glued to the screen - anything can happen.
That is how the game works as explained in the simplest words. To know about all the features of the game, you may need to refer to a full resource on the topic as the complete explanation is beyond the scope of this response.
Official release in India
As for the official release of this game in India, there are no clear announcements made so far. The developers have been worried with server stability given the popularity of the game in Asia. India has been added to the list of servers a couple of days ago which may be an indication of an imminent release in India.
However, if you are much fond of Pokemon Go and want to play it without even the official release, you may download the APK file from the internet and get set to the adventure.
Pros and Cons
Well, it brings the video gaming to the streets. What I mean by that is video gaming can no longer be blamed to make you a couch potato. Moreover, the game is being seen as a good tool to get rid of depression. People have been quoted as saying that they have become comfortable of going out and socialising.
As with the cons, the most important is the safety factor I pointed out above. Staying glued to the screen while moving around is indeed a huge safety hazard. Children should not be allowed to play alone outside your home. Another one, though of less importance is the battery drain you would experience on your phone. As the game involves using your GPS and camera, it is bound to drain your battery too fast.
Live....and Let Live!