I’ve learnt some really interesting stuff this week about how to design for different platforms. I face this problem a lot in my app as I am designing for both iPad and iPhone and I need two different basic modes of functionality for each. There are many ways that you can go about solving these design conflicts. Some people go for the lazy option and simply scale up an iPhone design to iPad. This can leave an interface looking chunky if the UI items are scaled up and sparse if the space in between them is scaled. This is not a good solution, as you need to design with the user and device first and foremost in your mind. The other solution is to use the classic scale up method of different view layouts. This is when you use a single view with a navigation bar to switch between views on an iPhone and a sidebar interface to switch between views for iPad applications. A classic example of this is the layout on the Mail.app included with both devices upon shipping. I don’t particularly like it as it has been used in so many apps that it has almost become too common making your app blend into the crowd. You need your app to stand out somewhat so that the users will remember the experience. I am yet to find a solution to this problem but I should soon with some careful thought.
There are some other issues as well which are not as commonly recognized when designing for different devices. One example of this is the way in which a user holds a device. With the iPhone, a teenager or adult sized hand should be able to touch with a thumb all the UI Items on the screen in any orientation without too much trouble. This is the common way that most users interact with the iPhone (though often when used on a table the forefinger is used for interaction). However, iPads are vastly different. When they are used on tables forefingers are generally used to select and interact with items. But when the device is held in the hand, it carries a decent amount of weight. This means that you must design to make sure that the user must not need to change the area of the screen in which they are interacting too often. Consider playing Fruit Ninja on an iPad while standing. It is not easy as you must precariously balance the iPad in one hand and swipe with the other. Your hand is constantly moving around the screen making it difficult to balance the device and distracting from the experience. Perhaps it is necessary for this game but it is a good idea to avoid it for a normal utility app. This is something that needs careful consideration and real world testing with mockups to ensure it is done right.