Here's how you can update the apps on your iPhone 5.
1. Tap on the App Store icon.
2. Tap on the Updates button on the bottom nav bar.
3. You'll see a list of apps that have updates.
4. You can tap on the Update button for each app, or you can simply tap on the Update All button to update all of them at the same time.
It's a good idea to keep your apps up to date on the iPhone 5, since many developers are now releasing updates that take advantage of the iPhone 5's larger screen size.