The PSP Minis are the PSP’s answer to the iTunes app store. Cheaper games with a 100mb size cap that you can download from the PSN store. While they’re cheaper than standard PSP games there have been some criticism about the apps due to a number of restrictions such as no updating the games, no multiplayer and no DLC for the games.
Even worse is that some of these games can easily be ported from the iPhone to the PSP with great ease, and often are more expensive on the PSP than they are on the iPhone. Now despite these downfalls there are reasons for all of these issues.
The lack of DLC, multiplayer and updating means that Sony would have to do quality assurance on the games much more often and look into them more due to the more features. The price of the games are up to the developer according to Sony, but the reason for developers choosing higher prices may be a result of platform.
With the iPhone or iPod touch you probably have something you can test it on, and developing for it requires a SDK which you can buy from Apple for either 100 or 300 dollars. I’m not sure how much the PSP SDK would cost, but I would think it would cost at least a deal more than the standard PSP or even PSPGo price, but that’s not the issue.
According to Gamasutra, the price of development for the PSP requires funding for two specific things. One is the aforementioned PSP SDK, the other is the cost to get the game rated for the ESRB, which is $2500 dollars. Even if a developer can easily port an iPhone game to the PSP, they still have to pay the premium for the ESRB, which you do not have to do for the iPhone.
Now the ESRB is trying to get iTunes to use their rating system for the app store, which would limit the number of new games released on iTunes, but would also make developing for the platform a much more expensive prospect.