One of the key differences between the D3400 and the existing D3300 is the inclusion of Nikon’s SnapBridge wireless image transfer technology, first seen on the Nikon D500. SnapBridge is designed to overcome the restrictions of conventional Wi-Fi, which is very effective for wireless image transfer and camera control, but is not an ‘always-on’ technology. Whenever you want to use it after a gap, you have to manually re-enable the Wi-Fi connection. SnapBridge gets round this by adding a Bluetooth LE (Low Energy) chip for a genuine always-on connection. On the D500, the Bluetooth takes care of automatic low-resolution image transfer to a smart device (perfect for Facebook and other social media), switching to Wi-Fi for full-resolution images and remote camera control. The new D3400 does not, however, have Wi-Fi, so the SnapBridge version included here is Bluetooth-only. You get the automatic lowerresolution image transfer to a smart device, but not fullresolution image transfer or remote camera control.