This may not be a surprise to many of the regular [NR] readers, but transferring Nikon D500 full size images with SnapBridge is very slow. Few weeks ago the German website heise.de published a follow-up on the Nikon D500 WiFi false advertising allegation in Germany. Here is the email I got from Andreas V. who originated the complain few months ago (see also his test data in the table above - click for larger view):
After the release of the iOS test I did serious tests by using a stopwatch and documented transfer times and battery usage, i.e. produced facts & figures, see this page (Google translation). My conclusion is that Snapbridge is an unsuitable technology selection for the transfer of original size image in terms of transfers time and power consumption. It may work for low res images as with the D3400, but this is not my user scenario - my scenario is using original size images only.
Unbelievable, but pretty simple to prove and reproduce, if you have the chance to compare different Nikon cameras and devices. I used the D500 with BLE and Snapbridge, the D500 with the WT-7 ( in the US WT-7A, RoW WT-7B, WT-7C) and the D7100 with the WU-1a. No rocket science, just some time, patience, an iPhone or iPad stopwatch and documenting the remaining battery capacity for all devices.
For low-resolution, 2 megapixel image transfer Bluetooth LE might be suitable, although transfer speed is limited to approx. 0.035 MB/s as the defaults specs. Of Bluetooth LE 4.1 simply do not allow any more. There so many sources available to the public, there’s nothing to prove. All scientific articles that I found are referring net transfer speeds of 236 to 270 kbit/s when using BLE.
When it comes to original size images SnapBridge still behaves according the specs, but 0.035 MB/s simply leads to long transfer times and high power consumptions. Battery drain is obvious and can be measured by everyone, who tries to transfer 15 or 20 original size images.