Local vs cloud storage
Also known as: on-device vs cloud, cloud storage vs device storage, local storage meaning
Local storage is the fixed physical space inside your device that holds files even offline. Cloud storage is online space on a provider’s servers that you reach over the internet. They are separate pools — adding cloud storage does not enlarge the device, and a full device can coexist with an empty cloud.
- Local = fixed on-device space; cloud = online server space
- Separate pools — one does not add to the other
- Cloud frees the device only when it offloads originals
Two separate pools
Your device’s local storage is a fixed amount set at purchase — for example 128 GB or 256 GB — and you cannot add to it on most phones. Cloud storage is a subscription pool that lives on remote servers and is shared across your devices.
These do not borrow from each other. Buying a larger cloud plan never frees the device, and filling the device never touches your cloud quota. Confusing the two is the most common reason "I bought more storage but my phone is still full."
When the cloud helps local space
The cloud only reduces local usage when a feature actively offloads originals and leaves smaller copies behind — such as iCloud Photos’ Optimize Storage or a cloud drive’s on-demand mode. Plain sync keeps full copies on both sides and saves nothing locally.
A practical split is to keep what you use often local for speed and offline access, and let large archives live in the cloud where they do not weigh on the device.