What are the different design approaches/UX considerations between designing an iPad app and an iPhone app?

First, and most obviously, you need to consider the constraints of both platforms. The primary constraint when you are designing an iPhone app is screen size. You have a smaller "canvas" to work with, and that constraint means that you can't overload the UI with an abundancy of controls and information. Not to say that you can "go nuts" when you are designing for the iPad, but you do have some more area to work with… you shouldn't overdo it there, either.

(Another general piece of advice is to get a good understanding of the UI conventions and controls for both devices by studying the iOS Design Guidelines from Apple… so that when you decide to "break" any of these conventions you will at least be able to do so in an informed intelligent way).

Second, if you are building an iPad version of an iPad app, you may want to "reverse engineer" the experience of the iPhone app, to identify what works and what doesn't. What are the core tasks that the app lets the user do? What can be done to enhance or improve these tasks when designing them for the iPad? Test the existing app with users, even if it's just casual "guerrilla testing." You may find that tasks and user needs that work perfectly fine in the mobile context on an iPhone make no sense on the iPad.

Case in point: I design banking and financial service apps, and one of the big new features that all the newer apps are providing is called "Remote Deposit Capture." What is that, you may ask? It's basically the ability to take a photo of a check and deposit it using a mobile banking app. It's universally well regarded by customers and a "delighter"… but it's hardly used on the iPad versions of different mobile banking apps. Why? My theory is it's just easier to take a picture with an iPhone than with an iPad, and the "awkwardness" is reducing usage and perceived value. You may find many features that "make sense" on the iPhone that don't on the iPad.

The opposite is also true, of course… there are going to be some features that don't work in an iPhone app but would work great on an iPad. Any feature that involved "drag-and-drop" as an interaction model, for example.

And for goodness sake, don't use the added screen real estate to add more features and information just because you can! Approach the design of the iPad application with the same discipline you would use when designing a small-screened mobile app. On second thought, use MORE discipline because the temptation will be greater.

Finally, a thought on behavior and context: Many of the best apps on the iPhone are designed to support "quick" behavior – you go in, you do something, you get out. This is because the iPhone is a mobile phone and when people use it they are often… well, mobile. The iPad is a different creature altogether. Though I HAVE seen people walking around city streets using an iPad to do something as they traverse crowds, it's a rare occasion – people do that with iPhones all the time. iPads are used a lot more for "browsing" and so the best apps on that platform provide a simple interface to consumer and interact with content.

Obviously, everyone and every app is different… but you should really look at what people want to do and where they do it first and foremost… no matter what platform you are designing for.

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One of a kind.

There’s going to be no shortage of words written about Steve Jobs. I never met him, never knew him. And yet…

I have to write something, more words to add to the rest. Because I’m compelled to.

Steve Jobs died today, at the age of 56. I could spend some of these words detailing what he did and who he was but you already know that stuff. I dare say, that if you are alive today and have had any exposure to technology or mass media, you know who he was. His impact and mark is obvious, historic and cannot be diminished.

I want to spend some words writing about what he believed in.

Like I stated, I never knew him, never met him… and yet, I did know him. His passion, his aesthetic, his values around life and design… He was a man who worked really really hard to made things better. He made technology accessible and by doing so he made people happy. His company was founded to makes products that lets people do more things in a better way. He was uncompromising, focused, and his vision changed the world. He looked at other company’s banal ideas and technology… and showed then how to make things elegant. How to do it right.

I understand such passion. I appreciate it. And… I share it. That’s what I do, too. My job is to design software and make it useable, useful, better. Will I have anywhere near the impact he had? Not a chance. But his passion is my passion and I will continue to work to make things better for people, one moment at a time.

I’ve seen Steve Jobs called “one of a kind.” We are ALL one of a kind, every one of us. We all have the same 24 hours in each day. The measure of a man is what you do with the time you have – the only currency we really have to spend. Steve Jobs made the most of his time, and I aspire to do the same in my own life. I think we all should.

When my Dad died last year, I said that “we are what we leave behind.” Dad left a mess. Steve Jobs leaves a legacy, one that time will not diminish. He used his time on this Earth well. Was he perfect? Of course not. No one is. But Steve Jobs left the world a better place than it was before he was here.

Thanks, Steve.