Just a few ideas that occurred to me while installing this.
Mainly for an eventual 'version 2' as I don't think you'll be able to implement them easily currently.
For the most part it i's painless to install, but in comparison to other home automation / internet controlled hardware, there's a few things that could be done differently. Not necessarily better, just differently.
1). Part of the install says 'label any important wires'. Sensible. The NEST thermostat, which has to be the benchmark for easy install has a small sheet of labels to wrap round cables for this purpose, in the manual. Cheap, and a nice touch.
2). The NEST also has 2 self tapping plasterboard screws to attach it, no need to use plugs. The Iro may be a little heavy to use these, but it might be worth considering.
3). The NEST (last mention of it, I promise) has a mini level for the backplate built in. Hardly a requirement for a box that's going to live in a garage out of sight, but like the other points, something that adds to the install experience.
4). Backplate. It would be nice to have a little more usable space in it, to store a little more slack in cables.
Clearly a clever idea, given the constraints of the hardware, but slightly erratic.
It worked for me on the fourth try - which is fine. Full brightness on the phone, darker garage, job done.
Something you might want to look at is the Belkin WeMo, which has a similar problem - needs to have a network configured, without a display - It comes up as its own network which you connect to via its smartphone app, then you send it the details of the network it should be on via the app, it reboots onto those details, job done.
Saves on the cost of the light sensor, at least.
Every other device I've seen, you connect to via ethernet, and configure that way.
Just some thoughts, for what little they're worth.