theres a few ways to monetize a f2p game on the app store. i've seen some of the studios claim they've made 50k a day when you factor in advertising/data and item/currency sales. i've seen some smaller app makers claim they've been lucky to make 50k in lifetime sales.
with smart cookies coming and so many firms poping up to specialize in game data gathering for mining to make in game monetizing easier/more fool proof, the possibility of making money in the space is increasing. especially with how over zealous advertisers are to get into mobile ad space, the amount their willing to overpay already is amazing to me.
it changes constantly. some developers claim to be making a killing with a game in the top 250. i've seen others say they earn dismal amounts and have a app in the top 150 or 100.
(a facebook game, but its interesting to read and fits the app store for many, to give an idea:
http://techcrunch.com/2012/04/18/kixeye-lucrative-dark-horse-facebook-gaming/)
the app store is really about pricing and how you choose to monetize your
type of game for maximum results. many don't seem to hit the right mix and falter in the end. it isn't as easy as throwing your app up for a dollar or going f2p with IAP purchasing.
many of the fp2 developers are trying to hit a certain number of products in the store at the same time. if they all don't break out to mega hits, fine. if you build a small, loyal audience, say 100k+. multiply that by 7 or 10, you can make money. its based on a model of inflation though with advertising that completely unsubstantial. its also based on whoring your loyal players for every dime you can get, in the turn, alienating most new players.
ad colony is selling a offline player where the developer can roll preinstalled videos into the app to play. usually with the player giving free currency for watching. the few apps rolling this out claim to be making a killing with ad dollars, yet... why? most of the apps are lucky to have 100k players listed on gamecenter. its usually the same 3 ad's repeating. kids watch the videos 300 times a day to get free items. whos really making money here? are advertisers being serviced?
as the technology gets better on the marketers end to monitor the activity of whats really going on with the ad space in game; i cant imagine prices not coming down. its a dollar bubble now.
this is why nintendo would be a disaster on the app store. they aren't built for the marketplace in any way possible.
they've never built a product from the ground up with the idea that it will be data/IAP/currency sales based. a good game on the app store that makes bank was built around those ideas. they can't even evolve animal crossing, the father to much of what we have now, to match the innovations that have been made in the genre. other than mario and pokemon, how many titles would be angry birds level. look at rovio's size/bank. how would nintendo take these titles over the top versus anything rovio has done with angry birds?
look how long its taken zynga to get a hold of the marketplace on iOS. even with well known IP from facebook. moneybags. they've just now been getting to a stride on the app store thanks to buying developers and studios who have had success on it. future success is unknown. there is little loyalty due to the size of the marketplace and the type of consumer your dealing with. i consider this THE wii audience so many on here love to bitch about.
the biggest success stories on facebook/iOS right now are smaller studios, with more niche titles serving an active but loyal membership. who will buy 30-50 dollar items. nintendo could have more success here with many of their games, they have an insta fan club who would download and play. yet at the same time, to attract these players who know the franchise and going this route, you risk turning off newer players/large exposure.
hopping into the app store for nintendo wouldn't be free money. you can have the best IP in the world, if you cant execute it properly, if your not built for the platform (something nintendo is very dependent on), it wont work.
seeing these japanese developers slap well known IP on the app store for 10+ dollars makes me laugh, how much do you REALLY think their making on that game? it isn't suited for the marketplace at ALL. yeah, it might make easy money. cheap port. usual the game is awful in turn. it also shows you how little they understand whats going on in the space. they have good IP and yet don't know how to build it on this platform for success. (eg, where the hell is my harvest moon iOS sim with IAP and currency whoring...)
this is with me excluding the fact that the app store is not mature enough to support someone the size of nintendo. they wouldn't be able to support that large of a development force on iOS. they'd have to get leaner and focus on more core titles. that alone would be a mess for them given the size of their catalog. they'd leave money on the table and not be able to service every franchise in a way they can on their own hardware.
this is REALLY why i do NOT want to see nintendo on the app store. it'd be a disaster for sometime. its better to nintendos own future to let them build and experiment with these newer ideas in their own setting. iOS future overlords or not, they have to.