"I've been in architecture for more than twenty years. I estimate how much and what resources will be required all the time. Nobody has been developing iOS apps that long"
I do not mean this as a personal attack or an insult aimed at you. Not at all. I've heard versions of this idea from others.
This is a really naive view of software engineering.
Recruiters are famous for firewall-ing good candidates because they think they don't qualify. The conversation goes something like this:
R: How much iOS experience do you have
C: Two years
R: Oh, our client requires three years
C: Sure, but I have 15 years of software development experience.
Most of it doing OO work on various platforms.
R: Well, sir, my client needs someone with three years experience in iOS, sorry.
I've had highly qualified friends not get jobs because of such ignorance. Whenever I've worked with recruiters I have made sure they understood my instruction to not filter-out anyone due to rigid metrics on the targeted platform. A good software engineers is far more than the "bling-bling" they happen to know about today.
I have been developing software and hardware for more than twenty years. iOS is just a new platform to work with. From the perspective of an experienced software engineer there really isn't anything particularly different, special or challenging about creating product for the platform. With such new landscapes it is down to learning the language and the API's and libraries available. Not a big deal. If you've been in this game long enough you've done that exact thing many times over.
In the case of an experienced software engineer, the idea that "Nobody has been developing iOS apps that long" somehow correlates to not being able to estimate time and costs is nonsense. Yes, one can draw from past experience and have a reasonable idea. And, yes, if you've been around, you probably resort to applying some multiplier to your estimate because, well, you've been there and you've seen what happens. And, yes (number three), you have to have invested some time (three to six months, that's it) to get into the new platform.
I've done quite a bit of building construction (tenant improvement and other major projects in commercial buildings). Estimating architectural projects can be far more accurate because in places like the US things are hugely standardized. Unless you are doing something way off the norm or run into snags everything is fairly well known and quantifiable. Foundation, framing, electrical, plumbing, low voltage wiring, A/C&Heating, drywall, stucco, paint, finish, install built-ins, flooring, etc. On the other hand, there are projects where you get hit with surprises that you could not have foreseen. I had the experience of doing a fairly large commercial TI project where we discovered that the soil had been contaminated with chemicals by the prior owner. It had to be removed properly and replaced with clean soil. Hundreds of truckloads of dirt were removed. This blew the budget right out to the moon.
Software is different in that, save language structures (if, for, while, switch, etc.) and patterns, everything can be different from project to project. And, of course, the other problem is that naive clients can inject features and functionality into a project that can easily double the amount of work required to complete it. Not to mention the lack of specs altogether.
It's like hiring an architect, pointing to a house down the street and saying "build me a house like that". Then, of course, no input or solid specs exist for anything inside or outside the house. This would be costly.
Or, even better, a client asking to build a house raised off the ground and supported by a single column, completely solar and wind powered. The client also does not want the solar panels to be visible from the ground or the wind generator's noise to be heard. The client also wants the house to rotate so that a room of his choosing faces the sunrise every day. They he scoffs at you for suggesting that this is going to cost more than doing a typical home design of average American specs. Oh, yes, he is happy to point out that he can hire an architect in Pakistan who will do the design for 1/10 of what it costs of doing a typical house design in the US.