iphone
I have an iPhone 5s (iOS 8.2) and an iPhone 6s (iOS 10.2). On the old iPhone I have a banking app which I'd like to copy securely to the new iPhone, including all the app's data. I do not want to make a full backup. Both devices are using the same credentials for iCloud, none of the devices is jailbroken.
The app does not use iCloud.
Is it possible to copy only this single app without using third party software?
Update: apart from iCloud selective app backup which implies that you need to fully restore the new iphone, you can use this to back up and restore only selected apps and app preferences that go along.
Otherwise create another backup of your old iphone, this time via using iCloud. (Settings > iCloud > Storage & Backup > Manage Storage). From the options on the next screen, choose which and app data you want to back up exactly. Then hit "Back Up Now".
Upon restore to your new iphone only the app data you selected during the icloud backup will be restored.
The best practice in storing app credentials is the Keychain. If you really need to recover the password check out this guide http://www.iphonehacks.com/2013/08/transfer-passwords-to-new-iphone-itunes-backup.html
In iTunes, go to the “Summary” section, scroll to Backups, and enable the “Encrypt iPhone backup” option.
After recovery, feel free to wipe the new iPhone.
In case the app did not store in Keychain, you can use this technique to migrate app data individually http://lifehacker.com/5891964/can-i-transfer-app-data-and-game-saves-from-my-iphone-to-a-new-ipad
Before we start, we should note this works for any iOS device. So if you want to back up and transfer data for iPads, iPhones, or between the two, this works. To manually backup and transfer data, we're going to use the free Mac and Windows program iExplorer. You don't need to jailbreak your iPhone to use iExplorer and it's easy to pull data from your iPhone to transfer it to your new device. Here's how to do it.
That's it, you're done. Different apps use different save files and occasionally the above process will require you to copy several files over. Other times you only have one file. This process works for most apps, but not all of them. Let's take a look at a few of the instances where data doesn't transfer over properly.
Don't forget to look at the caveats because sometimes this technique does not work.
Best Answer
Given the way online banking is designed you shouldn't need to copy local data for the app, as the app is usually just a client for their website. You should be able to simply download a fresh copy of the app on your newer iPhone, sign in to the app, and load all of the necessary data from their servers (recent deposits/withdrawls/transfers, share account info etc. would all be kept on their end and simply sent to your phone temporarily over the network when the app requested it, unless that is your bank uses a very unorthodox device-locked system, which seems both unlikely as well as unreasonable behaviour for a bank.).