How to manage multiple iOS devices
I know that using many Apple Devices is not so easy, and not so hard too.
You don't have to lose any data or download apps again just because you've bought another iOS device. Here are some ideas to transfer or sync your stuff across devices and also share with family and friends.
Getting a New Device?
Here's how to backup your apps and data before you move:
1. Sync your device to transfer apps. Connect your device to the computer and launch iTunes. Right click on the device name and select 'Sync Now'.
2. Right click on the device name again and select 'Backup'. This will save all settings, messages, photos, documents and saved games. Music, videos and apps are not part of this backup.
3. Once backup of your old device is complete, disconnect it and power on your new device. It will ask you to setup via iCloud or via iTunes. Choose to setup via iTunes and connect it.
4. Once drivers for the new device are installed, iTunes will give you the option to setup as a new device or restore from backup. Choose restore (the most recent backup is automatically selected).
5. Once data is restored, you can sync the device to get your music, movies and apps back. The first sync makes sure that your device stays up-to-date with all recent purchases/downloads.
Getting an Additional Device?
Here's how you can sync apps and data across them:
1. Connect and setup your new device by following the steps mentioned in the 'Getting a new device" section. This will start you off with all your data and apps on both the devices.
2. Enable iCloud on all your devices from Settings > iCloud > Storage & Backup. You get 5GB free and it automatically backs up photos, mail, contact, calendars, reminders, notes and settings.
3. In Settings > iCloud, select the services that you want to sync with other devices. For instance, you can uncheck photo sync if you have too many photographs on one device which will exhaust all storage.
4. Each time your iOS device is charging and within range of a known Wi-Fi network, it will automatically backup to iCloud. You can also perform a manual backup from Settings > iCloud > Storage & Backup.
5. On all the devices you own, go to Settings > Store and turn on 'Automatic Downloads' for apps and books. This way, all your new purchased items will be automatically synced across your devices.
Since it's possible that many device owners don't have a credit card, the only way they can get a paid app on their own Apple account is if someone gifts it to them. For instance, if your children have iOS devices, they can ask you to buy them an app. To gift an app, open the App Store on your device and search for the app by name. On that page, you will see a link that says 'Gift this app'. Click the link and sign in to your account. Click next and enter the email ID of the recipient. Note that this email ID doesn't necessarily have to be associated with that person's Apple ID. The amount will be charged to your card and the recipient will get an email from Apple with a link to download the app.
You can share apps with friends or family. There may be different situations when you want to do this. For instance, you may want to give someone else the benefit of using one or more of your paid apps temporarily. Before you do this, it is strongly advised to take a complete backup of all data and apps on both devices. Open the App Store on the other device and sign out of the existing account. Sign in to your account and click on 'My Apps'. From here, you can download as many of your paid apps without paying anything extra. Note that once you do this, all the previous apps on your friends device will stop working. The only way to get everything back to normal is to restore the device to factory settings using iTunes and recover all the data from the backup. Many users see this as only fair, since the App Store doesn't allow you to try apps before you buy and neither does it offer a refund for apps that you don't like.
If you share your device with others in your family, head to Settings > General > Restrictions to prevent others from installing or deleting apps and preventing in-app purchases (use it as a parental control). Typically, there's a 15-minute window after you make a purchase, during which the Apple password does not need to be entered again for another purchase. On the Restrictions page, you can set the password to be required immediately, for each purchase.