Many things don't work well together: oil and water, drinking and driving, and as it turns out, Samsung's TecTiles and the Galaxy S4. Samsung is acknowledging that the current line of NFC tags cannot be read by its new flagship phone. In fact, even the official TecTile site's Buy Now link is now defunct.
The SGS4 incorporates a Broadcom BCM2079x chip which lacks support for some types of MIFARE tags from NXP Semiconductors, including TecTiles which are built with MIFARE Classic chips. Samsung is planning to launch TecTiles 2 to replace the older stickers. Here is their official statement given to Android Police:
Samsung is introducing TecTile 2, an update to the original TecTile NFC programmable tags, which will be available in the coming weeks. TecTile 2 will use the current NFC technology on the market, allowing Samsung customers to further incorporate NFC into their daily lives and to use with the latest Samsung Mobile products and services, including the Galaxy S 4.
As industry standards continue to evolve, Samsung remains committed to meeting those standards and adapting its technologies if necessary. Samsung customers can also fully utilize TecTiles 2 with existing Samsung Mobile NFC-enabled Android smartphones currently in market.
Until recently, most NFC-equipped phones were built with the NXP PN544; that is, until Google replaced it in the Nexus 4 and Nexus 10 with Broadcom's competing chipset. This switch came at the same time as the introduction of Broadcom's Bluetooth and NFC stacks into AOSP. The NFC Forum has never officially recognized MIFARE Classic tags as a standard because they use a proprietary authentication and encryption format.
No technical details have been shared about TecTile 2 yet, but the new tags are likely to be NFC Forum Type 4, based on rumors that some may have already gone out to customers packaged as the original TecTiles. The new stickers should be compatible with virtually all NFC-equipped devices on the market, for both NXP and Broadcom chipsets. Specific release dates haven't been given, but we will keep you posted.
The issue was first noticed by Brian Klug from Anandtech