iPhone: The 7, 8 and X iPhones can read iTag digital tags with the iTag app found on the App Store
iPhone XS, XS Max and XR iPhones can scan NFC tags with or without an App
Android operating system 6 and higher are compatible without the need for iTag.com app. Most mobile devices using Android 6 and higher have capability for Near-Field Communication (NFC). You may need to first enable NFC. Do this by pulling down the settings menu from the top of the screen.
Devices using other operating systems may be compatible if they are capable of NFC. A third party app may be required such as "NXP Tag Info."