What Finder sync does
Apple's Finder sync copies content from your Mac onto your iPhone. For photos, you choose Photos or a folder, and Apple says the iPhone is then updated to match the albums on your computer. For music, you turn on music sync and choose your whole library or a selection. Syncing is for people who don't use iCloud Photos, and turning it off removes what was synced from the phone. If you subscribe to Apple Music, your library is managed through iCloud Music Library instead, and Finder's music sync is usually unavailable. The iPhone's Music app has no way to add a folder or import from the Files app, which is why this sync, or iCloud Music Library with a subscription, is the usual way in.
What iCloud Photos does
iCloud Photos is built so that your whole library is available on every device, and you choose how each device holds it. With Download Originals, the device keeps the full-resolution photos. With Optimize Storage, it keeps smaller versions and fetches the originals from iCloud when it needs them, optimizing only when space runs low and starting with the photos you open least. Apple: Optimize storage in Photos →
Either way, your photos exist in more than one place: in iCloud, where they count against a plan you pay for, and on your devices, in full or in part. That is reasonable engineering for "everything, everywhere". It just isn't what many people expect from the words cloud storage.
The common expectation is offloading: put it in the cloud so it isn't on my device. iCloud's model is closer to mirroring, with offloading as the fallback when a device runs out of room. A device with less space than your library either fills up with copies, or falls back to smaller versions and relies on a connection for the rest.
What streaming does
Raza Photos and Raza Songs leave your files on the Mac and serve them to your iPhone as you browse or play. Nothing is copied to the phone. Edits you make from the phone are written back to the original files on the Mac, so there is always exactly one copy that counts. It is offloading in its simplest form: the library lives in one place, and the phone shows it without keeping it.
Side by side
The differences decide how much space you use, what stays up to date, and which copy is the real one.
| Finder sync | iCloud Photos | Streaming (Raza Photos, Raza Songs) | |
|---|---|---|---|
| Copies on the iPhone | Yes, a full or partial copy | Yes: full originals or smaller versions, depending on the setting | No. Files stay on the Mac |
| Phone storage used | Grows with what you sync | Grows with your library, unless Optimize Storage keeps smaller versions | Only what the app needs to show you |
| Getting started each time | Connect and run the sync | Automatic once it's on | Open the app |
| Direction | One way: the phone is updated to match the Mac | Both ways: changes on any device reach the others | Edits write back to the files on the Mac |
| Works without the Mac | Yes, everything is on the phone | Yes for what's on the device. Originals that were optimized away need a connection | No. The Mac must be on and reachable |
| Which copy is the real one | Two copies to keep in step | The one in iCloud | One: the Mac |
| Where the library lives | Only the System Photo Library | Your Photos library | Any folders you choose |
| Live Photos | Lose their effect if synced back | Keep their effect on every device | Played as Live Photos, from the pair of files |
| Cost | Free | Free up to 5 GB, then a monthly plan | Free today. Any future price would be a one-time purchase |
iCloud Photos is about photos. For music, iCloud Music Library works differently and needs an Apple Music or iTunes Match subscription.
When syncing is the right tool
If you want your whole library on the phone for a long flight, or you spend time where your Mac isn't reachable, a copy on the phone wins. A small library that fits comfortably on the device is also a good case for it. Nothing about streaming beats having the file in your pocket.
When streaming is
A big library and a phone with limited storage. A family where several devices should see the same photos without each keeping its own copy. Two Macs that should look like one library. Or simply wanting to skip the cable and the sync step. Streaming spends no space on the phone and leaves nothing to reconcile.
Why we don't sync
It isn't that we can't. A synced copy takes space on every device and creates a second version of your library to keep in step with the first. Cloud storage, to most people, means moving things off their device, and a phone's storage is the one thing you can't add to after you buy it. So we keep one source of truth, your Mac, and stream from it, and your phone's space stays yours. The tradeoff is honest and simple: the Mac has to be on. How library sharing works →