Depends on you. If you want to buy a contract base then buy from there or if you want to buy an unlocked one then buy from India. You will get discounts on plans there if you have your own phone
Electronics items are cheap in Canada and moreover lots of offers come in December month.
but initially the cash you will be having has to be used for many other expenses,
so I will say you should take phone from India along with you.
I you are looking for a new mobile then you should purchase it in Canada
You get 1 year warranty, you can also look for mobiles on contract basis in Canada.
If you purchase mobile in India, then the warranty is not valid in Canada. Unless it's you get an International Warranty.