I came across this last week and found it very useful for copying pictures from my iphone direct to my network storage drive.
Apple products may be brilliant if yours are all Apple. However, I have an iPhone 4s and and have always had the problem of getting pictures from it to my Windows desktop.
Photostream was erratic on what it transferred and the sequence it put them in. I could not rely on it at all and it stopped working on later versions of their operating system so I gave up on it.
Itunes was initially written to sell music and move it from the PC to to the Ipod. The camera on the Iphone really is about moving pictures the opposite way and it is a shame they didnt rewrite it. I dont have any music on my iPhone
The iTunes "Sync" scares the hell out of me as I have no idea what it is going to copy and which direction. It managed to sync the blank Outlook diary (which I never use) on my pc with that on my iPhone (which I use all the time) completely wiping all entries. I have far more space on my pc for photos so why would I want to have all of them on my Iphone too. I am not clever enough to use Itunes so I don't.
Instead I have transferred pictures when I get back from a trip by linking my phone to the pc and copying them all across with Windows explorer. Its a pain. Main problems are that the iPhone stores pictures in folders with strange ids which it make them difficult to find and they all come across upside down and need editing after.
A few months ago I added a network storage drive (WD mycloud Mirror). This has two identical disks so I felt it better to transfer all pictures to this in preference to the pc. This makes the transfer even more of a pain so I looked at going direct from the iPhone.
WD have their own photo app and it is dead simple.
However, when you check the you find that changes the name and date of them all.
Their forums show the complaints from 2013 and nothing has been done, but I did get the tip for the app above. Its simple and intuitive and you can see what you are copying, where its going, and when its done. One product for all your devices.
My luxury is that I have been able to copy all this years pictures to the NAS, then view them on my large TV in the comfort of my lounge (not this app) while editing out the dross using my phone! Very pleased.