[mordrax]

From the author's pov, it's an interesting proposition. Take sorcery for example: http://www.amazon.com/s/ref=nb_sb_noss?url=search-alias%3Dba...

I bought this and played it for about an hour to completion. For my hour, I'd have made them $0.12. Instead, I paid $4.64.

So for them to get to the same profit using this model, they'd have to attract $4.62/$0.12 = 38 times more users. i.e instead of having 1000+ downloads, they'd need to be in the 38k+ downloads range and for everyone to have played it to completion.

I see two problems for this particular game. 1. Fighting fantasy based games are a niche market so is there going to be a large enough user base to support this? 2. I'd say that the length of a typical gamebook shouldn't be more than 1-2 hours as it will get very complex. So they're kind of capped re per player usage.

Since it's a niche market, I don't imagine there would be hundreds of thousands of people trying this out for 5 minutes each.

[zrgiu_]

remember that you paid $4.64, but 30% of that went to Amazon anyway. Generally, about 2-3% of the people who would download a free app would also pay for it, which could make Underground a good choice. People who haven't paid though, aren't as invested, and are more likely to quit using that app sooner.

Also, there's the niche issue: it's very possible that fighting fantasy fans are more likely to pay for their apps, which means none of these numbers applies to them.

[zephyrthenoble]

There are also a lot of people out there who would not be willing to pay the $4.64 dollars. By using this model, developers can get both the people who want to buy it through the store and people who don't want to spend any money to play it, which might end up being more total profit.