Lightning iPhone: camera adapter, power, and the 'Accessory update' loop

On a Lightning iPhone, use a Lightning to USB 3 Camera Adapter with a charger plugged into the adapter’s Lightning port. The charger powers the board and the iPhone.

Which iPhones work

The ESP32 Agent app needs iOS 18 or later. That means iPhone XS, XR, or newer. iPhone X and older can’t install the app.

USB-C iPhones plug the board in directly with a short USB-C data cable and don’t need this page. Lightning iPhones need the adapter, because the board needs a USB port that acts as a host.

Connect it

1. Plug the Lightning to USB 3 Camera Adapter into the iPhone.
2. Connect a USB-A to USB-C data cable from the adapter’s USB port to the board. A charge-only cable won’t work.
3. Plug a charger into the adapter’s Lightning port.
4. Attach the antenna to the board and keep it near the phone.

With the charger in place, the iPhone charges while the board runs.

When the board gets no power

Without enough power through the adapter, the board doesn’t start:

• The board’s LED stays off.
• The app can’t find the board in Plug Me In, and no pointer appears on the iPhone.
• ESP32Agent-… doesn’t show up in Settings → Wi-Fi.

Check that the charger is plugged into the adapter’s Lightning port and switched on, then reseat the adapter and the cable.

iOS keeps asking for an accessory update

Some adapters, on newer iOS versions, keep showing that the accessory needs an update and never power the board. Waiting or reconnecting doesn’t help.

• Try another Lightning to USB 3 Camera Adapter.
• Make sure the charger is in the adapter’s Lightning port, so the board is powered from it directly.
• Use a known-good data cable between the adapter and the board.

If the board still stays dark, write to [email protected] with your iPhone model and iOS version.

More: Hardware & buying and the FAQ.