You can also control which files will be included in future back-ups. If I tap my iPhone in the Backups list I can see a list of every app that I have on my iPhone, and how much data each app will store when I back-up my iPhone to iCloud. You can click the green button to turn off back-ups for individual apps, and as you do this you'll see an updated count of how large the next back-up will be.
Manage iCloud storage: Removing back-ups to make more space
After your Photo Library, one of the biggest items that most people upload to iCloud is the daily back-up of their iPhone or iPad data. By default, iOS automatically backs up your iPhone or iPad to iCloud once a day (as long as the device is turned on, connected to power, and connected to a wifi network). But if those back-ups take up too much space on iCloud you can simply turn off the back-up function altogether.
Tap on Delete Backup and you'll see another little window pop up that asks if you want to 'Turn off & Delete'. If you go ahead and do this you will delete any back-ups from that device that are already stored in iCloud, and also turn off any future back-ups as well. You can still back-up your iPhone or iPad by connecting it to your Mac or PC and using the automatic back-up option in iTunes, but those back-ups are stored on your computer's hard disk so they don't take up any of your iCloud storage.
Manage iCloud storage: Upgrading iCloud storage
If these space-saving tricks still don't stop you from hitting that 5GB limit then you might just have to bite the bullet and pay for some more storage. Apple's pricing for iCloud storage used to be ridiculously expensive - which is why so many people still use rivals such as Dropbox or Microsoft's OneDrive. However, Apple cut the prices of iCloud storage quite drastically last year, following the introduction of iCloud Drive.
Go back to the main Storage panel and tap Buy More Storage, and you'll see a price list for the different iCloud storage options. You can upgrade to 20GB - and that's 20GB total, not 20GB on top of the original 5GB - for just £0.79 a month. There are also plans for 200GB at £2.99 per month, 500GB for £6.99, and 1TB for £14.99. Rivals such as Dropbox, Google Drive and Microsoft's OneDrive are still cheaper - with Microsoft and Google both offering a really handy 15GB of storage for free - but the simplicity of iCloud and its ability to seamlessly share all your important files and data across multiple devices is really useful if you own a lot of Apple products. And, of course, you can use more than one cloud storage service if you want. I mainly use iCloud for syncing photos and emails across my devices, but I also have a free Dropbox account that I use as an emergency back-up for important work files on my office Mac.
Sign up for CIO Asia eNewsletters.