October was the month the iPhone 4S debuted. Since October, Sprint subscribers have been complaining about the data speeds of the new iPhone 4S. Several owners have been reporting dismal 3G download speeds of less than 1mbps.
Spring has been bulking up its network over the last few weeks, rolling out improvements to enhance iPhone performance. Sprint says that initial customer response to the improvements seem to be fairly positive, but a few users are still unsatisfied.
Customers are reporting issues experiencing 3G download speeds as low as 70kbps. As you can imagine, this would make downloading applications a nightmare, and using Siri nearly impossible.
I recommend to research Sprint's performance in your area before purchasing an iPhone 4S.