Quick answer: an offline upscaler ships its AI models inside the app and runs them on your phone’s chip, so the photo never has to leave the device. Local Photo Upscaler works this way for all four modes. You can check it yourself by turning on airplane mode and enhancing a photo.
Cloud versus on device
| Cloud upscaler | On-device upscaler | |
|---|---|---|
| Where the model runs | The company’s servers | Your iPhone, iPad, or Mac |
| Your photo | Uploaded, processed, stored for a period | Stays in your library |
| Needs internet | Yes | No |
| Model size | Can be very large | Limited by device memory |
| Typical pricing | Subscriptions or credits | Often one-time |
How to check an app is really offline
- Turn on airplane mode (and make sure Wi-Fi is off).
- Open the app and enhance a photo.
- If it completes, processing happened on the device.
Also check the App Store privacy label. Local Photo Upscaler’s label says Data Not Collected.
The trade-offs
On-device processing has limits. Phones have less memory than servers, so Local Photo Upscaler caps upscale output at about 17 megapixels and processes the image in tiles. On iOS 1.1.10, very large photos may be processed at a smaller size on devices with less memory; check the actual output dimensions. The app is also a larger download (about 316.5 MB) because the models live inside it. And cloud services can run bigger generative models, which is why they sometimes produce more dramatic face results.
What still uses the network
Downloading the app and updates from the App Store needs a connection. The app itself has no account, no ads, no analytics SDKs, and no photo-processing backend. This website uses Google Analytics for page visits, which is separate from the app and described in the privacy policy.
