You’re most likely familiar with the process of signing into iTunes, downloading your app and running it. If not, there are many helpful tutorials available on the Apple web site. Note that Windows users must download iTunes from the Apple web page and install it separately.
iTunes provides a mechanism for sharing files between your desktop and iOS apps that are specifically designed to do so. TheSky uses this file sharing mechanism so that astronomical database files from your main computer can be copied to the iOS device.
Plug your mobile device to your computer. iTunes should start automatically, if not, launch iTunes now.
Depending what device was plugged in, tap the iPad or iPhone button located on the upper right side of the iTunes window, below Search Library.
Hint: Be sure to click directly over the iPhone or iPad text on the button. Clicking the graphic that shows an underlined arrow pointing upward, or the Eject button, will disconnect the device. If you accidentally click this graphic, unplug the device and plug it back in again.
Click the Apps button to reveal the Apps pane.
In the Apps column under File Sharing, highlight TheSky. You might need to scroll the iTunes window to see it.
Click the Add… button.
Open the Downloads folder.
Choose the desired database, and click Open.
Figure 10 shows the optional PGC and UCAC 3 databases that have been copied to the iPad.