Now that Rare Earth has been out for a few months, I’d like to take a look at some of the data that’s been gathered from players, as well as reflect on the implications.

Analytics have been a big part of the Rare Earth experiment. I used Flurry for this. It was incredibly easy to implement (they actually have a Windows Phone SDK!) and free.

That said, the service isn’t perfect. For example, according to Flurry, 6308 people have downloaded Rare Earth. Microsoft’s App Hub statistics say the number is 10617. Assuming Microsoft is right, since they control the servers and all, Flurry is missing a full 40% of users.

Even so, the numbers should be good enough to draw some conclusions. Let’s get started!


Between 6308 users and 1503 new games, 7811 solar systems have been created

A reported 16660 play sessions

15478 new planets have been created

9359 planets were consumed by stars (judging by some reviews, this often wasn’t intentional!)

79211 asteroid waves have entered, as well as 105450 comets

4840 star upgrades have been purchased

56 stars have reached the end of their lives (version 0.6 introduced stellar evolution, and has only been live for a few days)


379 users have discovered life, and have nurtured its existence on 1024 planets

Beyond the initial required spark to the single-cell organism stage, users have also used the spark to shortcut to:

  • Plant-level 289 times
  • Animal-level 368 times
  • City-level 360 times
  • Space-faring-level 251 times

Curious that people generally skip forward in the middle stages most, rather than the highest level (which takes the most time to advance naturally)

2702 gamma ray bursts have torn through systems with life

1819 of those GRBs have caused mass extinctions

In other words, 67% of GRBs were fatal, which indicates the difficulty for this obstacle is quite high. I’ve received this feedback independently from several players, but this data really crystallizes that

3170 rockets have been launched from space-faring planets (about half of which were planet evacuations)

Only 275 have successfully landed and colonized planets (~9%; perhaps space-faring life is due for an intelligence upgrade?)


6113 orbits have been normalized (a surprisingly popular feature – maybe the standard controls could use with a bit of “assist” if the difficulty is so high that people happily trade valuable earned orbits for more-stable planet orbits?)

A dismal 11 people have clicked on the referral for BuildDown. Is the game not appealing to those in the market for a gravity/life sim/arcade game? Or do people just ignore the About menu? Actually, I can’t tell. I didn’t hook menu transitions, so I don’t have the data to answer that question. Big oversight, and lesson learned for next time!


34101 invaders have made their way into systems

8594 were shot down

I figured a fair number of kills were accidental, as invaders in early versions used to get tripped up around stars and crash themselves.
However, since they were upgraded to avoid stars a few versions ago, the kill rate has actually improved, which shows that the only thing holding players back before was their enemies’ own stupidity

Before the feature was removed, 9383 “orbits for matter” transactions occurred. While a popular option, ultimately it hurt balancing for other orbit-powered features, like life and orbit normalization. Instead, I’m trying other ways of making more matter available to players

The email feedback button was pushed 211 times (my inbox says 72 people went through with it, and I really appreciate all that incredible feedback!)

Even with the inaccuracies, these analytics have been very helpful, providing another dimension of insight to complement the impressive volume of marketplace reviews and feedback emails.

Great Artists

Good artists copy, great artists steal.

– Steve Jobs, by way of Picasso (maybe)

Steve Jobs famously appropriated this quote, and it’s been used, out of context, to justify all manner of evils ever since. It has been twisted to mean, “Do what it takes to be successful, because history remembers the winners, not the innovators.” Watch this video of that famous line again, though:

Steve Jobs (and Picasso) are not actually telling people it is okay to outright steal. They’re reminding us to learn from the best. Build off their successes. Improve. Iterate. Not claim someone else’s inventions as our own, but use our limited resources to deliver new value instead of reinventing the wheel.

I’m going to take a page from his book and steal his quote, with my own spin:

Good artists copy, great artists incorporate.

– Kevin Tarchenski


Space is a subject I’ve been in love with my whole life. As a kid, I dreamed of growing up to be an astronaut (far later in life than most kids would consider normal).

From my childhood bedroom

As a game designer, fully half of my prototypes have something to do with space – as a setting, theme, or even a character. Still, it’s something I’ve struggled to express in gameplay. Initially, I just wanted to replicate the cool, dynamic visual of moving through space on a cosmic scale, the kind of thing they do on the typical Discovery Channel show or NOVA special.

Space physics prototype

But I also want to create games that reflect my personality, and that’s a little hard to do with an n-body physics simulation. So I kept experimenting.

One of the concepts I found myself repeatedly drawn to is a mix of strategic management and tactile action. I decided to pursue that idea with a game about creating and managing a solar system – small enough scope to be practical on a phone, but complex enough to yield a rich field of possibilities. That’s what I’m working on now.