NeuroVis

Support

NeuroVis is an interactive convolutional neural network visualizer for iPhone. Draw a digit and watch a real CNN classify it, layer by layer.

Frequently asked

The app opens sideways.

That is intended. NeuroVis is landscape-only — the network runs left to right and needs the width.

Does it need an internet connection?

No. The model weights and sample images ship inside the app. Nothing is downloaded and nothing is uploaded, ever.

My drawing gets classified wrong.

The model is a deliberately small CNN trained on MNIST, so it is accurate but not perfect. Draw the digit large and centered in the square. Lowering the channel count or switching the activation function also weakens the network on purpose — reset to defaults in Settings if predictions look off.

What do the colors mean?

Blue is a positive activation, magenta a negative one, white is near zero. Tap any tile to open the detail view, which shows the exact numeric range.

Can I change the network?

Yes. In Settings you can set 2–10 channels, a 3×3, 5×5 or 7×7 kernel, one or two convolution layers, and ReLU, sigmoid or tanh activation. The network recomputes on device each time.

How do I reset everything?

Settings → Reset. This restores the default network, clears any hand-edited kernel weights, and resets the language to your device default.

Privacy Policy

Last updated: August 2026

NeuroVis does not collect, store, transmit, or share any personal data.

• The app has no account system and requires no sign-in.
• The app makes no network requests. All computation happens on your device.
• Digits you draw stay on your device and are never transmitted anywhere.
• There is no analytics, no tracking, no advertising, and no third-party SDK of any kind.

App preferences (language, network settings) are stored locally on your device and are removed when you delete the app.

Because no data is collected, there is no data to request, correct, or delete. If you have a question about this policy, email woganglai@gmail.com.