Of course, as with the best laid plans, this strategy didn't go the way I expected. While I am receiving consistently higher downloads of the free version as I had been getting on the paid version, I was expecting the userbase to grow by significantly more than it actually did. I needed to do some thinking before I could wax lyrical about the exposure opportunities for free games.
I'll begin with my starting logic: offering your game for free should make it more open to recommendation, and hence benefit your exposure. Let's think about why.
Put yourself in your customers' shoes, or look at your own purchasing decisions. I presume I am not an atypical iOS user, and from my own experience even paying 69p for an app requires a big decision. After all, how many times do I want to spend 69p before I find something that I really enjoy? Unless I am cautious about my spending those 69p's could really add up!
When I buy a cup of coffee, I know exactly what I'm going to get and have a fairly accurate estimate of how much I'll enjoy it. So paying £1.80 for my medium Americano is not a big decision. With a game I have only the vaguest idea how much I'll enjoy it, even if I take time to read all the copy, see the reviews and look at the screenshots. In short, I'll be taking a risk.