Currently their are more than 20 Cryptocurrency exchange working in India from where you buy/sell ALT Coins like XRP, BTC, NCASH, TRX, LTC, ETH, DASH, 
Looking to current world exchanges hack news specifically hackers stealing the coins from users account so you need to be cautious. I have been analysing Blockchain and Crypto world since 2013, as my experience and analysis I will say to go only for these 2 exchanges Koinex & Zebpay
As these exchanges have high quality hack proof security and best to do trading in India.
If you are interested in reading which coin is best to invest please let me know and how to do trading to make quick money ask me your question I would be happy to answer your questions.
Most Important - Market knowledge is very important which you very much essential. That you can have only when you have Cryptocurrency news app even that app which provide you the news 1st and fastest having 100% genuine news not the fake news. My suggested best app is “Crypto Crunch App” - Download Link: - http://onelink.to/ax6vy2