IPhone 6s Apps are not being shown in iTunes on Windows 10

Solution 1:

If all you're wanting to do is clear space on your iPhone and you want to know how much space each app takes up, you can do this all directly from your iPhone as follows:

1. Go to Settings
2. Swipe up and tap on General
3. Tap on Storage & iCloud Usage
4. Under the Storage heading (not the iCloud heading), tap on Manage Storage
5. Give your iPhone a little time to calculate how much space each of your apps is taking up
6. When finished they'll al be listed from largest to smallest

Now you can tap on any 3rd party app to see a breakdown of its data usage or to actually delete the app altogether.

In the case of Apple's iOS apps, tapping on them will give you various options depending on the app.