Most of the modern smartphone with Android, iOS or other OS are compatible with this specific feature. Technically, it's enough that your second device has a camera to scan the QR code, while the process to follow to scan this might be slightly different according to the platform used.
Please note that you don't need any Snapcall application to have access to this feature, in fact what you need is a Camera app and a browser installed on the device.
In case you have an iOS device, here are more in-depth instruction on how to scan the Snapcall QR code:
Open the Camera app from the Home Screen, Control Center, or Lock Screen.
Select the rear facing camera. Hold your device so that the QR code appears in the viewfinder in the Camera app. Your device recognizes the QR code and shows a notification.
Tap the notification to open the link associated with the QR code.
In case you're using an Android device, the process might vary according to the phone or app used. The instructions below apply to most of the smartphone in the market:
Open your Camera.
Choose an option to scan:
To scan with the QR mode of Camera from Google, tap QR, and point your camera at a QR code.
To scan with your camera's default photo mode, point your camera at a QR code.
Tip: You can’t scan a QR code in portrait and video mode.
To open a browser page, app, or payments app after a QR code is scanned, click the banner that appears.