There are a growing number of accessories that use the microSD card standard as storage for photos and videos. These tiny cards can store up to 200GB on a card the size of a fingernail, which explains their popularity in action cameras like the GoPro and on a growing number of drones. Leef now has an iOS microSD reader called iACCESS (US$49.99) that speeds the transfer of video and photos from your favorite cams to your iPhone or iPad, and can also act as virtually unlimited storage for your device by simply popping in other cards.
iACCESS uses a "J" design similar to the company's popular iBridge USB/Lightning storage device, but it's a bit wider on the vertical part of the "J". That width is apparently there for stability of the iACCESS when connected, as well as providing a place to hide the card reader electronics.
There's only one connector, of course -- an MFi-approved Lightning connector -- and then a tiny slot for the minuscule storage card. Plug the Lightning connector into your iOS device, place the microSD card in the slot, fire up the Leef MobileMemory app (free), and go for it.
The MobileMemory app has been refined over the years and is now a nice, clean looking app for transferring, storing and viewing content on the card. I did have one glitch -- while going through the five-step "tutorial" for the app and iACCESS, the app crashed hard! It essentially shut down my iPhone, which I'd never experienced before with a card reader. However, all worked perfectly after powering up my iPhone again, so the problem was only temporary.
The app and card work beautifully together for backing up action camera content to an iPhone or iPad, or just viewing recently-shot content on the iOS device. This is something you can always have in a pocket or pack; it weighs just .2 ounce (5.7 grams) with the microSD card installed.
Any transfers will be only as fast as the card you have installed in the iACCESS; a standard card I was using was dreadfully slow, while I'm sure that many of the new microSD XC Class 10 UHS-1 cards in higher capacities would show much better performance.
For lightweight and compact viewing of action cam or drone footage from microSD cards, the iACCESS is a very capable device. Transfer speed is dependent on the microSD card you're using, so I recommend getting the fastest card you can. Leef's MobileMemory app is easy to understand and is very iOS 9-like in looks, a great companion to the hardware.