How NFC Updates Work
HPzenAi Smart Tags update by tapping an NFC-enabled smartphone running the HPzenAi app directly against the tag surface. The phone's NFC field transmits the new content wirelessly, and on battery-free models it also supplies the energy needed to refresh the E-Ink display. The display update completes in 1–3 seconds and the new content remains on screen indefinitely — no battery, no power, no connectivity needed to retain the image.
Requirements
- 1NFC-enabled smartphone — iOS 13 or later, or Android 6 or later.
- 2HPzenAi app installed and signed in.
- 3Tag within 3–5 cm of the phone's NFC antenna (battery-free models) or within 10 cm (billboard model).
- 4For HPZ-ST-BILLBOARD-DISPLAY-1: battery charged above 10% via USB-C before updating.
Writing Content to a Tag
Use the HPzenAi app to select a content template, fill in the details, then tap the phone to the tag to write.
- 1Open the HPzenAi app and tap Smart Tags in the main menu.
- 2Tap Write to Tag.
- 3Select a content template: Price Label, Product Info, QR Code, ID Card, Shelf Label, Billboard Notice, or Custom Text.
- 4Fill in the content fields — text, price, name, QR code URL, or image as required by the template.
- 5Tap Prepare Update — the app compiles the display image and readies the NFC write payload.
- 6Hold the back of the phone flat against the tag surface with the NFC antenna area over the tag.
- 7Keep the phone still and do not lift it until you feel the vibration or hear the confirmation tone — typically 1–3 seconds.
- 8The app displays an Update Successful message when the write completes.
Finding the NFC Antenna on Your Phone
The NFC antenna position varies by phone model. If the tag does not respond immediately, move the phone slowly across the tag surface until the update begins.
- 1iPhone: NFC antenna is at the top of the device — position the top third of the phone back over the tag.
- 2Samsung Galaxy: NFC antenna is in the centre of the device back — position the middle of the phone back over the tag.
- 3Google Pixel: NFC antenna is in the upper-centre of the device back.
- 4If unsure of your phone's NFC position, check the manufacturer's specifications or search online for your model.
Updating Billboard Tags (HPZ-ST-BILLBOARD-DISPLAY-1)
The LiPo-powered billboard uses its built-in battery to drive the larger display refresh. Follow these additional steps for the billboard model.
- 1Confirm the billboard battery is charged — charge via the USB-C port on the tag if the battery indicator is low.
- 2The billboard NFC antenna is located behind the display panel — position the phone NFC antenna directly over the display area.
- 3The NFC update range for the billboard is up to 10 cm — greater than battery-free models due to the larger internal antenna.
- 4Hold the phone within 10 cm of the billboard display until the update confirmation is received.
- 5The billboard display refreshes with a full black-white cycle before showing the new content — this is normal and takes 2–4 seconds.
- 6The billboard can be updated while wall-mounted if the phone can be positioned within range.
Performing a Full Display Refresh
A full refresh clears display ghosting and resets the E-Ink pixels for a clean image. Do a full refresh whenever you notice faint remnants of previous content.
- 1Open the HPzenAi app and navigate to Smart Tags.
- 2Select the tag you want to refresh.
- 3Tap Full Refresh.
- 4Hold the phone against the tag as normal — the display will cycle through black and white before showing the refreshed content.
- 5A full refresh takes 2–4 seconds, compared to 1–2 seconds for a partial update.
Tips for Reliable Updates
- 1Always use the latest version of the HPzenAi app — updates include NFC optimisations and new content templates.
- 2Keep the tag surface clean and free from metallic stickers, foil labels, or conductive materials that block NFC.
- 3Do not attempt NFC updates through thick card, metal shelving, or metal door frames — these absorb the NFC field.
- 4For high-volume retail environments, assign a dedicated staff tablet or phone for tag updates to maintain consistent NFC antenna positioning.
- 5After any firmware update to the HPzenAi app, perform a test write on one tag before updating your full tag inventory.