I have been buying online products from flipkart from last 2 years and flipkart has never let me down I have orderd shoes, electronics, t shirts and everything was a good quality product the customer service of flipkart is bit slow but quiet helpful it resolves the matter at the end of the day.
I have bought 4 phone from the flipkart till now and I didnt have a single problem with them so far.The quality of the product depends on the seller which is selling its product on flipkart so it not flipkarts falut if the product comes in damaged state of low quality but flipkarts resolve this problem aslo by returning the damaged product and giving either a replacement or refund.
The delivery time take around 5 day in my area but sometimes it also deliveries in 3 days only so kudos for that flipkart .
The app and the website is well designed and very easy to use .flipkart has been really good for me for past 2 years so I would like to say its a reliable website