If you backup to your iCoud, you also need to backup to your iPhone to iTunes on your computer, I think, but the files backup on your computer cannot read.
Tutorial: How to Backup iPhone Apps to iCloud?
Step 1. Open iPhone. Press the home button for a few seconds to open your iPhone.
Step 2. Connect iPhone to Wi-Fi
Tap Settings from the iPhone's Homescreen and press Network in the Settings screen. Then tap the WiFi button and slide the slider to "on". To connect to a public network, just tap the network name and you will complete connecting iPhone to Wi-Fi.
Step 3. Enter ID and Password
Enter your Apple ID and password to log in the iCloud.
Step 4. Sync apps from iPhone to iCloud
In iPhone, go to Settings, also you can try Vibosoft iPhone backup extractor
program, and select iCloud item. In the Storage&Backup window that appears, turn on the 'Back Up to iCloud' iCon. Then click "Backup Up Now" to backup iPhone apps to iCloud or : try How to extract iPhone from backup