Is it legal to trade forex from India?
I'll try to explain briefly. In order to trade in Forex one has to convert currency first because there are no interesting pairs with rupees (in fact, there are pairs with rupees appearing now but they are not going to be very popular among Forex traders due to a number of factors), but in India there is no free conversion of the national currency! Luckily, RBI has been softening foreign exchange rules in recent years and now every Indian is allowed to exchange rupees for up to 200,000 USD per year without giving any justification. So one can say - voila, any Indian can trade in Forex for this amount now.
But RBI guidelines say that Indian citizens cannot use this 200,000 allowance for margin calls. What is a margin call? Margin call is the amount you put on your balance at the Forex broker! So basically, you cannot transfer money for Forex trading, even though you can make transfers in general.
So what are the options?
Semi-legal option is to specify other reason of transfer - instead of margin call, you call it "investment in futures" or whatever. I call it semi-legal because you're going to lie, but on another side - it's not going to be possible, at least not that easy, to verify.
Another, absolutely legal option is to ask a friend of yours who is either a NRI or a foreigner to transfer money for you, because they don't have these limitations.
There is also a "grey" option - to use online currencies like e-gold. They are not regulated by any government, legally speaking - they don't exist. So you can use them without breaking any laws, but your government is not going to help you in case of problems with broker - you simply won't be able to prove that you had any money on account.