Problem with NFC

Hello! In my app i need to read tagid via NFC.
But when i run APK (or run via Companion) and put NFC tag behind device, i got question from Android - which app i want to run to read tag. And it’s happens on main screen and other screens. It impossible to read tag.

I have Android 9 on Galaxy Fold, same problem on Galaxy S9. What i do wrong?

Of course i put Near Field component on Screen1 and place logical block “whean NFC.tag read”…

With Galaxy S5 and Galaxy S7 I tested, I have the same problem.
Update july 2020: I had the same problem but formatting a NFC, with NDEF format, solves the problem.

1 Like

Do not test in companion but as apk. Appinventor warns for this behavior.

IMPORTANT: Applications built with the NFC component will not respond to tags while in live development mode. To test your application, you must build your app and download the APK to your phone .


Hi. Same here. App not working. Unable to read NFC tag with created app.(apk downloaded and istalled). Pls help. No app choice for reading tags.


  • Are you using pre-formatted NDEF NFC tags?
  • Show your blocks.

Thx for reply. i need only to read NFC tag ID.2020-03-02 (2)

  • Did you use a preformatted (NDEF) tag?
  • Did you test it with the APK, and not within the companion?

yes and yes. i have no option to chose app for tag reading.

@misos Did you already try to use the Appinventor NFC example: Cup Game?
Import this and make an APK. See if this works for you.

Do you find solution to this? i have same problem.

@bidonek Did you try out the example Appinventor NFC example: Cup Game?

Yeah, i am, but this example utilize message written to tag not its ID. In event block when Near_Field.TagRead are blocks named tag ID and massage. Massage works but tag ID show nothing.

Show your blocks

so I am having the same issues, has anyone found out how to suppress these Android Pop ups?
I made a little Test apk but it couldn’t solve the problem.

1 Like

Any updates on this topic? I have the same problem…I feel like it is MIT AI2’s bug because,

doesn’t work.

1 Like

sadly no.
I have put my project on hold until this is fixed.
Also semmes kind of funny to me that this topic has gone under the radar for this long now.

Best Regards

It is not a bug, it works but you have to take every step in the right order, in the right environment. For instance use a NDEF pre-formatted tag otherwise it fails.
NFC failure is not due to Appinventor nor Kodular.
If you want you can get paid support, to find out what step fails.

You have ** not used** a pre-formatted NDEF tag. That is why you get the question which app you want to run!

If the example does not work, you made a mistake or your NFC chip in your phone is broken.

The chips are not broken, it works with every other nfc app. Also, I tested with all 3 cards I have and none work.
Note: all 3 are different models.

1 Like