Indeed. This has changed. Any device with bluetooth has always supported bluetooth game controllers. It's simply that there was no input API (Direct Input, SDL, or whatever the iOS API happens to be). Both this and the cost associated with the device has changed. In addition, my iPhone was $100... Plus a 2 year commitment, at a reduced rate (saves $20/month) due to the bundling under my Verizon "OnePay" FIOS/Wireless household plan. I know it's complicated, but you get the point that it isn't as expensive as it seems.
The last time I checked, smartphones with HDMI out were rather expensive (>> $100) and didn't work with control pads (I never really cared about smartphones though, so this may have changed)