Information Technology Reference
In-Depth Information
Only public non-beta versions of iOS and OS X are supported. You won't be able to ask questions about bugs or
features in beta releases.
Getting Started with Xcode
When you enroll in a program, you are allowed to access a page like the one shown in Figure 2.8. The design
may differ, but the page includes a download link to the latest SDK (Software Development Kit).
Xcode is packaged as a standard Mac .dmg file, which is typically around 2 to 3GB. You must download the
complete SDK with each new update; there's no incremental install or upgrade option.
A complete upgrade cycle may require extra downloads. A new version of iTunes is often released around the
same time as Xcode is updated. OS X also may go through an incremental update.
iOS developers need to update the firmware in all their devices—or at least, in all the devices that need to run
the current version of iOS. Documentation may need to be downloaded separately.
TIP
If you have a spare older device, it can be useful to keep an older version of iOS on it and use it for compatibility
testing. Conversely, if you have a single device such as an iPhone, you may be reluctant to upgrade it to beta firm-
ware for testing. Older apps typically work on newer firmware. However, apps developed for new beta firmware
don't work on devices with older versions of iOS, unless you deliberately make them compatible.
A full update can easily require 5 to 8GB of files, including Xcode, firmware, documentation, iTunes, and OS X.
This is impractical over dial-up and can be difficult with slow broadband. If you don't have 10MB/s or faster
broadband, it's useful to plan updates so you can leave the download running overnight.
Mac developers have a more straightforward experience. OS X is updated less frequently and doesn't usually re-
quire extra downloads. Individual OS X beta releases are released approximately monthly, but are much smaller
downloads than a full iOS beta. The differences between minor versions—for example, OS X 10.7.1 and
10.7.2—are often so small that you can develop apps without keeping up to date with them.
FIGURE 2.8
In this example, the download link appears at the bottom left. This location often changes.
