Working on Family Gamer TV, I've used a variety of different approaches to create episodes over the last six months. Being new to the field of video creation, I started by hiring a friendly local professional photographer Tim Pestridge. He shot the first few with his Canon 5D MkII SLR and a shot-gun microphone grabbing sound directly. The results were impressive, and lent proceedings a high production feel even though they were shot on a single camera.

As time has gone by I have realized that although there's no substitute for this kind of quality on a studio shoot, being out and about grabbing interviews with developers and family gamers meant I needed something more portable.

As I mentioned in my Stop Motion post, this led me to purchase a decent tripod and Glif clip to enable me to record head height interviews with my iPhone (as well as try out stop animation with the kids).

This was all well and good but the iPhone's built in microphone, although not bad, wasn't up to the task of recording audio at distance. The hunt was on for a mic I could use to enhance the audio quality of these mobile recordings.

First I tried plugging a standard microphone into the iPhone jack; I soon discovered that this doesn't work. This led me to Chuck Lawton's in-depth review of the iRig microphone. This not only enables you to plug a stick mic into the iPhone jack but also gives you three sensitivity settings and the ability to monitor sound via the pass-through headphone socket.

I used the iRig microphone for a while and it is a good low cost option. However, because there's no pre-amp in the setup and you can only have one input going into the iPhone I've found this quite limiting.

A solution about to be released is the iRig Pre, that will enable you to plug in a stage or studio mic to the iPhone and provides powered amplification. I have one of these pre-ordered for when they release in a couple of weeks (and will check back with a review).

While I wait for that to arrive, I've been trying out another solution to my iPhone sound problems - the Fostex AR-4i ($129.99 on Amazon) and have been very impressed.

This is a housing for the iPhone 4 (and iPod Touch using the supplied adapter) that provides both amplification, the ability to plug in two microphones at the same time as well as mountings for a tripod and flash. It essentially grants the iPhone all the inputs that a high end digital camera has.

The Fostex comes with two mini-microphones that can sit on top of the unit to capture a stereo recording. Or, as I have been doing, you can plug two clip mics (from $4.99 clip micsAmazon) in and use one for the interviewer and one for the interviewee. Because this is recorded to separate tracks it gives me a great deal of flexibility in the edit.

The top of the Fostex provides an LED read-out of the sound level so you can see if it is clipping. You can also plug a headset into the bottom (and adjust its volume) to monitor sound recording in real time. Finally, there is also an iPhone app (iTunes) that lets you control how the Fostex AR-4i processes the sound. This includes the input levels, low cut filter and limiter setting.

The build quality of the Fostex is also very good and offers a mounting point for a light or flash on top, as well as a universal tripod thread on the bottom. I would have preferred if the threads were mounted in metal (rather than metal mounted in plastic) but still they served their purpose well.

It has the feel of a well thought out piece of kit. For instance there are extra inputs on the side for the microphones and a tripod thread on the bottom that enable you to shoot video and record sound in portrait orientation as well as landscape.

It also comes with a metal grip that can be attached to the bottom of the unit to offer a hand hold. I now use this to add a little height to my tripod setup (pictured), and was pleased to find the grip had an appropriate thread at each end.

The only other down side is that currently the iPhone 4S has to be in Airplane mode to avoid sound interference – something I actually already do having found it interfered with the iPhone's in built mic. I contacted Fostex about this and it is apparently an issue that will be solved with the next version of the firmware.

As with all these things the proof of the pudding is in the eating (or the recording in this case). This is a test recording I have created that lets you hear the following setups:

iPhone built in Microphone

iPhone with iRig Microphone on different settings

iPhone with Fostex AR4i on different volumes and microphones.

The Fostex AR-4i has become an essential bit of kit for my mobile recording. It not only solves the problem of attaching my iPhone to a tripod in a secure way but it also provides the ability to plug in any standard jack based mic.

On top of that it enables you to record stereo audio to the left and right tracks separately. Finally, the ability to monitor the sound levels and adjust the gain on the fly while recording has also been a big help.

I'm aware that the iPhone is in no way unique in its ability to capture high definition video, and I have achieved similar output from a variety of smart phones over the years. However in terms of the range of peripherals and add-ons like the Fostex and iRig products, the iPhone is very well served. It also means that I can take advantage of the iPhone 5's improved camera (when it is released) without having to buy any other new kit. Currently this means I'm more than happy with my Apple-centric setup, although I'm happy to be persuaded otherwise.

The Fostex AR-4i is available from Amazon for $129.99.

A sample unit was provided for review by the manufacturer.