The four configurations of iOS apps

The ubiquity of iPhones and iPads these days means there is great app support and variety for these devises. But you would think that an app running on an iPhone or iPad would work on either devises because they are running the same OS – Apple’s iOS. This is not true. To make things worse it isn’t explained to users, at least, how apps relate to the hardware either in the App Store or elsewhere.

So here is my summary.

There are four configurations for apps in relation to hardware running iOS.

  1. Universal app
  2. Separate iPhone and iPad apps
  3. iPhone only app
  4. iPad only app

A universal app is one that runs on both iPhone and iPad with a single purchase. That is, if you bought it on either your iPhone or iPad it will be available to the other device without extra cost. Furthermore, the design adapts to the hardware. The use interface UI will look and behave differently depending on hardware is an iPhone or iPad. Here are two screenshots of the same app. The first is running on an iPhone and the second on an iPad.

An iPhone or iPad specific (for the lack of a name) app is one that is available for both the iPhone and iPad but require the user to purchase both separately. One has to be careful as to which version to buy. If you purchase an iPhone specific app it will work on your iPhone as it is designed to. It will also work on your iPad but the design will not adapt to the iPad hardware but will make your iPad look like a huge iPhone. But if you had purchased an iPad specific app be aware that it will not run at all on your iPhone even though the developer has made both versions available but as separate purchases. So if you want to run this app on your iPad either purchase the iPhone version or else purchase the separate iPad version.

iPhone only apps are apps which are available for iPhones only with no separate iPad apps made available by the developer. There are various reasons for this. The most common or likely reason is that the apps are designed specifically for the form and functionality of iPhones. Here is a screenshot of a notetaking app for the iPhone. Not only does it not have a ipad equivalent it only works in portrait mode with the keyboard positioned for single hand inputting.

Finally, iPad only apps are ones that are designed for and are only available for the iPad with no iPhone version purchasable. These apps are designed specifically for the tablet form with way to make it work on iPhones. The reason here again is about form, functionality and practicality. Below is a screenshot of a drawing app designed to work on iPads alone. The small size of the iPhone screen will make drawing impractical. But other drawing app developers may beg to differ and design either a universal or separate version for the iPhone as well.

There are reasons why you may want an app to run on both your iPhone and iPad. Mine is that having access to certain productivity apps on my iPhone means I will always have a backup to use in case my iPad dies on me during teaching. But even if this doesn’t matter you should be aware of your options when making purchases on either your iPhone or iPad. The compatibility designations are anything but transparent.