Amazon is the biggest brand for online shopping. customer service is very good and there toll free number is available 24x7. Amazon provide quality products as amazon have Prime option. Amazon provide guranteed one day delivery options also but most expensive they take 100 rs for one day delivery, that is very high. Amazon app is very helpful and very fast as its interface is very easy and user friendly. amazon is worlds largest brand it is trusted world wide no need to worry about anything.