we're developing industrial hardware and we've added a ISO15693 standard NFC chip to it as parameter memory. We're writing an Android app for users to show and change these parameters and the app works fine with nearly all Android devices tested so far.
We additionally plan to have an NDEF record with a url in it on the chip so that users not having the app yet are directed to a website telling them about the app.
Now we have bought a Z4 with Android 7 (but the issue is not Android 7 related, as a Nexus 5X with Android 7 works) and as long as the URL NDEF record is on the chip it cannot properly read out the chips memory. Not even with the demo app of the chip manufacturer. If we make the NDEF record invalid by setting the first few bytes to FF, we can successfully read out the chip memory.
When reading out a ISO15693 tag via Android one gets the chip serial number automatically and this always starts with E0 and a manufacturer code as 2nd byte. When the NDEF record is there it is sometimes properly read out, means E0 and manufacturer code are correct, but most of the time the complete serial number is shifted by some number of bits to the left. In case of 2 bits the ST demo app claims the chip is not from ST but Matsu**bleep**a, in case of 1 bit it's said to be from NXP and in other case it's "unknown" manufacturer.
The very same issue happens with an older and smaller Sony Tablett of a colleague of mine (Kitkat), but it doesn't happen with a Sony Experia T Android 4.3 Smartphone!
Since one cannot do anything to change that basic tag reading in the Android API (at least as I'm aware of) the issue needs to be in the Z4.
How to get this sorted out with Sony? Or what can I do from our side to get it fixed (besides not storing an NDEF record on the chip)?
