Once you've locked the iPhone and case into the hand grip, it's easy to hold the entire thing with one hand. The Snappgrip has a good feel to it and counterbalances the weight of the iPhone well. I have rather small hands and had no problem using my index finger to press the focus/shutter button or toggle the zoom. I did find that I needed to use my thumb on the aptly-named thumbwheel to move it to the different setting detents.
The Snappgrip is paired with the iPhone through the iPhone app -- you cannot use Bluetooth settings to pair. Turn on the Snappgrip and a blue light flashes to indicate that it is disconnected; tap the Bluetooth button in the Snappgrip app and pairing is done with just one more tap.
I had issues getting the Snappgrip to pair consistently, meaning that after I turned off the device and disconnected, the next time I turned the device on and tried to pair it indicated that the iPhone and Snappgrip were communicating, but they weren't. The only way I could get the two talking again was to turn off the Snappgrip, kill the app, go into Settings > Bluetooth and "forget" the Snappgrip, and then go through the pairing process again.
Fortunately, Snappgrip inventor Lee Harris was able to give me a quick response and noted that this happens on occasion when there are a lot of low-energy Bluetooth devices in the area. Sure enough, I had a number of such devices in the area, and so getting to a location where the only two Bluetooth devices were my iPhone and the Snappgrip resolved the issue. Harris also says that an app update later this month should help resolve the issue.
The app is in portrait mode, which is a little odd given that most of the images I was shooting were in the comfortable landscape orientation. As such, you the controls are sideways when you're looking at them. For shooting, you have single-shot, continuous, video, scenes and timed shot modes. The scenes mode provides a choice of night, portrait and landscape modes, while timed shots can be set up to take the picture 5, 10 or 20 seconds after you press the shutter button.
Snappgrip's app has its own photo library so you don't fill up your Photo Stream with pictures. Images can be shared to Facebook, Twitter, and Instagram, or emailed. An "Effect" button provides a way to add tags to an image, select from 18 different filters (one of which, Soft Focus, crashed the app every time I tried to use it), add a number of borders from a button confusingly titled "Sences", adjust color saturation, add some frames (most of which just get overlaid on the image rather than framing it), crop the image, create a simple collage, or apply a bokeh effect. Unfortunately, the slider for the bokeh effect disappeared before I could adjust it, making that effect basically worthless. There's another button for exporting images to the iPhone album, and a last button for deleting a photo.
While I was impressed with the quality of the hardware (with the exception of what seems to be an overly-sensitive Bluetooth chipset), the app appears to me to need some definite work. Since the app first made it to the App Store in November of 2013, it has been updated six times for "bug fixes". It's good to see that Harris and his team are working on fixes, but the app has a long way to go before it will be as useful as other photography apps.
Snappgrip provides a much-needed accessory for iPhone photography in that it adds a comfortable and usable hand grip. However, issues with Bluetooth conflicts and the app made it problematic for me to use it for a lot of photography. If you have very few Bluetooth devices and can put up with the quirks of the app at this point, you'll find Snappgrip to be a very useful tool for turning your iPhone into a "real" camera.
Rating: 2-1/2 stars out of 4 stars possible