iPhones get a much bigger subsidy from the carriers. This can be deduced from the ASP that Apple, HTC, RIM etc report. iPhone ASP has always been $600+, while HTC, RIM have ASPs around $300-400 (Samsung smartphone ASP is even lower). This can also be seen by looking at contract prices outside the US. For example, in the UK all phones can be had free on contract, but the monthly amount you pay for an iPhone is much larger than for a top of the line Android (see the O2 or Vodafone UK sites).
The reason this is not reflected in the contract-less prices is because US carriers have a very strong incentive to inflate them to force you to choose contracts.
The reason this is not reflected in the contract-less prices is because US carriers have a very strong incentive to inflate them to force you to choose contracts.