FAQ: Why do I see a random UID number when reading an Android pass

If your VTAP reader is set up to read both NFC passes and cards/tags you might notice that whenever an Android phone is locked, or has its display switched off, it will interact with a card reader as if it is an NFC Type4 tag, with either a fixed or random UID, such as '08E22AC1'.

The VTAP will always first attempt to read a mobile pass, but will fail to find a VAS or SmartTap device, because the Android device cannot respond in this state. If reading NFC Type4 cards/tags is enabled on the VTAP, it will then move on to try reading this type of card and when it appears to find one will report that UID.

For this reason, we recommend that you only enable reading NFC Type4 cards/tags when they are a necessary part of your application. If you do need to read both NFC passes and NFC Type4 cards/tags, you should make use of the IgnoreRandomUID setting, available from VTAP firmware version v1.1.12.4.

Latest firmware for VTAP readers

If you need to update the firmware on your VTAP reader you will find the latest versions on our downloads page.