BuildDown, Monetized

Part 2 of a discussion of game design decisions made for BuildDown. Part 1 is here.

BuildDown is a simple, action-oriented game, which made it somewhat challenging to figure out how to monetize. There are no levels, so I can’t exactly sell more content. The mechanics are not friendly to puzzles to force such a content model, either. Instead, I had to weigh the various popular approaches to see which played best to the strengths of the game.
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Voyager, like all my games, is free to play and was designed to be supported by in-game advertisements. So far, players have responded very positively to the game. Unfortunately, my bottom line has not.

So far this month, about 300k ad impressions have been served to Voyager users. This chart breaks down those percentages by region:

From this perspective, it appears the game has been most successful in Asia and Europe (and my App Hub download numbers, Flurry analytics, and the huge number of positive reviews from those regions corroborate this). This next chart tells a different story:

In terms of revenue, many of the regions where the game is the most popular barely chart. In fact, almost 80% of the revenue earned in that period comes from just 12% of the total impressions.

Why is this happening? The answer is eCPM. eCPM means “effective cost per thousand impressions,” and it’s what determines how much money a developer makes from ads. An eCPM of 1 means that 1000 impressions earns the developer $1. The value can vary wildly, from a few cents to several dollars. Unfortunately, because I’m using Microsoft’s ad control, “a few cents” is often overly generous.

This complex chart demonstrates the relationship between impressions, eCPM, and revenue. The further to the right a country is, the more impressions, while height equals higher eCPM. Finally, dot size correlates to revenue. Notice how most countries have an eCPM at or near 0, including many with highest number of players.

I’m thrilled with the amount of support and positive feedback I’ve been getting from abroad. Ultimately though, what this boils down to for me is that unless my game does better in the US, UK and Canada (or unless Microsoft gets its act together with worldwide advertising), it’s never going to make money (on Windows Phone, anyway). I’m still surprised it hasn’t done better in the US, but I can always hope that it will someday get featured and attract the audience it needs to thrive.

The Worse Bug

Rare Earth is not profitable. Let’s get that out of the way up-front. The game was released as an experiment to see whether the mobile games platform would be receptive to an unfinished (but frequently-updated) game concept. In many ways, the experiment was a failure. Users were extremely divided about playing an unfinished product (almost all the reviews were either 5 stars or 1 star), and there were nowhere near enough users to generate enough impressions to make any money off the game. Or so I thought.

Here’s a graph of my impressions for June and much of July. Rare Earth is just one of the pack among the 3 ad units from BuildDown:

However, when I was finalizing the latest Rare Earth release (v0.6), I noticed an oversight on my part.  had programmed logic into my ad control wrapper to detect errors, wait a bit, and try to recreate the ad control, in an attempt to recover from any crashing issues in Microsoft’s ad control. Unfortunately, I had forgotten a critical component – to actually call my update logic! Ultimately, any ad crash caused the ad control to stop functioning until the game was started up anew. I had no idea I was missing out on potential impressions until I fixed the bug. Here’s the same chart, with another two weeks added in:

Well that’s interesting. Flurry tells me there hasn’t been any significant uptick in my userbase or number of sessions. Isolating for the variable, that means I have a 5-20x upgrade in my number of impressions just by compensating for errors in Microsoft’s ad control! Extrapolating backward, Rare Earth could have been sitting on hundreds of thousands more impressions over the two months it’s been live.

I’m sure there’s a lesson in there somewhere.


Conventional wisdom is that only the most polished and complete games are successful on mobile phones, but some guys made a rudimentary implementation of Pictionary and sold their company for $200 million, so screw conventional wisdom. I’m going to try something different.

In a few days, Rumor Games will be releasing Rare Earth on Windows Phone. It’s a project I’ve been working on for a long time (in mobile game terms). It started as a prototype to see what kind of fun ideas would come from playing with orbital mechanics. Over the last few months, it has grown and changed, leading to several spin-off experiments. But the core mechanic of flinging planets into orbit was something I wanted to see through, and while the experiments were fun, none really brought it to the next level of excitement that I was looking for. Usually, a prototype like this would end up shelved and never see the light of day.

Now, I’ve followed other peoples’ projects that seemed interesting and fun from the outside, but ended up being canceled for one reason or another. Maybe the sales projections weren’t quite where they needed to be, or maybe the product just wasn’t gelling right. But my interest was real and genuine, and I absolutely would have tried them, and would have supported them if I saw promise in what I tried. And with the low barrier to entry of mobile, why not let people try?

All of this led me to this experiment. I’m going to release Rare Earth as-is – beautiful, but unfinished. There are no tutorials, no music. But there is an opportunity. I’ve included a (to my knowledge) one-of-a-kind voting feature, to empower players to help direct future updates. I hope people will see as much promise in this game as I do, and I want to hear from them about what excites them the most.

I want to start a conversation. Email us. Tweet us. Write reviews for the game. I promise I’m listening, and I promise I’ll keep working on Rare Earth as long as there is interest. In the meantime, we’ll keep working on our Next Big Thing.