[jayvanguard]

I've also done a ton of cost estimation and I thought this was a reasonably good approach for capturing the "core cost" of development of an app.

What it doesn't capture is testing beyond just design-code-unit-test such as multi-device testing, user testing, user acceptance testing, etc. and all of the change management that goes hand-in-hand with that.

[fullwedgewhale]

I think that argument is only correct if you have fairly well understood pieces of work. I'm going to build an another on-line social recipe app. People type in recipes, they share those recipes, make comments on those recipes, maybe review the recipes, etc. I think their metrics break down very quickly when you start doing more interesting things like, taking automatically finding similar recipes based on the descriptions of the steps in the recipes. Or maybe performing a recommendation of recipes based on a user's rating of recipes.

Or, for that matter, correctly internationalizing the recipes and conversion of measurement units. (You don't want to have add 3.43272 cups of flour to 0.2347 gallons of water, when translating metric to imperial - you'll need logic to scale up/down quantities and round within a given tolerance - which is often narrow when you start baking pastries). Or there might be a service for this specific example that I'm not aware of, but the point is when you go beyond a very narrow scope, I believe this tool breaks down.

[jayvanguard]

Very true. It doesn't leave any room for exploration of requirements or the usual customer waffling.