But, before we wrap this project up, we’re hoping to get one more round of new users by releasing EfZ on the web. You can play the latest version here on our website.  We have also put up the game up on:

• Kongregate
• Game Jolt
• Chrome Web Store

We’ll be looking to add more, but the main concern is finding sites that allow the use of the Unity Web Player (rather than converting the Unity game into a Flash game: currently the Unity -> Flash conversion does not support some features that we need for EfZ).

Hopefully, we’ll get some more plays in April, and be able to make some conclusions in our research study.  Stay tuned!

So, in early January (on the 10th), we switched EfZ to free for about one week (just over 6 days).  In the app description, we added text to indicate that the game was on sale for a limited time.  As you can see in the graph below, going free resulted in a lot of installs (a total of 7,689 copies of the free version were installed during the sale), and after the sale ended, we did see a bump in paid sales (compared to our pre-sale averages).  Before the sale, we were averaging 8 sales per day, and after the sale ended, we averaged 9.8 per day for the rest of January.  By the end of January, we had a total of 283 paid sales (which was better than our December total).  That’s not a lot, in absolute terms, but it is helpful as we look to recoup our modest development costs.  In February, sales have settled back to their pre-sale levels (or a bit below).

 We were also hoping that using the sale would improve our sales rank on Barnes & Noble, and it did: we went from a rank of about 10,000 up to a peak of about 1,200.  Since then, we’ve settled back to about 2,255 (as of today).  Also, the game’s rating on BN did suffer: before the sale we had a solid 4 star rating, which has slipped to about 3.5 as we got a lot of new comments.  Some of the critical comments seemed off-base (one of the 1-star ratings had a comment that indicated the reviewer had not even finished downloading the game! ), but many of the critical reviews did point out problems (with the controls, graphics, etc.).  We were glad to see that a number of people seemed to like the game, and of our 55 reviews, 29 gave it 5 stars).  People seemed to either like it or hate it (with 5-star and 1-star reviews being the most common ratings), and I wonder if that is a factor that depends on experience with video games (and with 3D games).

Since EfZ is a research project, you might wonder if we now have enough data to finish our study (with over 7,000 new installs).  And the answer is: nope.  While we had a huge response to the sale, most of the people who submitted our basic demographics (age and gender) indicated that they were less than 18 years old.  For ethical reasons, we cannot use data submitted by minors, without parental approval.  Since the median age reported by these users was 12, that means most of these installs will not result in useful data (for us).  But, seeing a number of younger users pick up the game when it went free was not a surprise (and seeing the typical age of one of our users helped us take the negative reviews we were seeing with a grain of salt!).

• Android Market – 664
• Mobango – 528
• SlideME – 468
• Amazon – 11
• AppsLib – 736
• GetJar – 3

For a total of 2,410 installs of the free version.  And, we had one paid install from the Android Market, and 8 from the Amazon Appstore (besides our sales on the Barnes and Noble Nook, which we’ll describe in a future post).  These numbers also include SlideME, where we published the full free version near the end of January.  One thing I should point out is that we put money into advertising the Android Market and Mobango versions, so most of the installs in both markets were driven by ads.  So, for us, the best markets in January were AppsLib and SlideME (especially since EfZ was only on SlideME for about a week in January).

Also in January, we spent some time working to get some reviews of EfZ to help publicize the game, and in the end we were fortunate enough to receive two: one from Android Zoom, and one from Tablified.  Both reviews were thoughtful and accurate, but they were not glowing or enthusiastic (and so, were unlikely to drive new installs of the game).  After we saw these reviews, and the weak performance of the game on the Android stores, we decided that EfZ was not going to succeed with our current strategy.  We knew going into the release that EfZ was simple in design, but we hoped that it would attract some interest because of its unique origins (as a research project).  But, as of mid-January, it looked like we were not gaining any momentum.

So, at the end of January, we turned Chapter One into a free, full version of EfZ (with banner ads), and left the ad-free version out for $0.99.  Our hope is to get more people to try the game out this way, and perhaps drive a few sales of the paid version.

Our next (and probably last!) move is to release web versions of EfZ.  We hope that the game (which will look better in a browser than it does on mobile devices) will help us promote the game, and drive installs of the mobile version.  We’re not sure when the web version will be ready, but we hope to have it out by March at the latest.

To quote the article:

“Over and over again you read articles online that tell you that games are Skinner Boxes, and that if you can just figure out the reward system, and the way to give the food pellets back to the player to press their pleasure center, they will become addicted and they will play forever and ever,” said Radoff.

While Radoff doesn’t dispute the idea that there’s some amount of conditioning that occurs for certain aspects of games, that’s not what provides depth to gameplay or makes things interesting, and Radoff finds it surprising that game developers continue to take the concept of the Skinner Box so seriously when mainstream psychology left the associated theories by the wayside decades ago.

As a psychologist (and one who spends a considerable amount of his time training rats in Skinner boxes) I would say that operant conditioning (the type of learning focused on here) has certainly not been left by the wayside in academic psychology.  And, in reading this article, I was reminded of another (also published on Gamasutra, back in 2001) that described very clearly how operant conditioning could be applied to video games.

But, I would certainly agree that video games bear very little resemblance to Skinner boxes.  By design, a Skinner box is almost the most boring place you can imagine.  A small box, made of metal and plastic walls (See the image below, from the Gamasutra article).  Typically, each box is equipped with a dish for delivering bland food and liquid rewards.  And, they are often equipped with a couple of lights, and levers a rat can press to obtain food.  If the rat presses the lever, rewards will usually be given according to some schedule.  That is pretty much it.

Image from Behavioral Game Design

But, with this simple device Skinner and other behavioral psychologists have been able to carefully study different schedules of reinforcement (the rules used to reward lever pressing) and how these schedules affect the behavior of rats (and humans).  This research has lead to some pretty straightforward take-home messages.  If you want an individual (human or not) to respond consistently, and at a high rate, then it is best to use a variable ratio schedule of reinforcement: each time the individual responds, there is a random chance that he or she will get a reward.  If you want an individual to respond in frantic bursts, then use a fixed ratio schedule (where you have to respond a certain number of times before you get the next reward).   If you want a person to respond a low, but consistent, rate, use a variable interval schedule (where you have to wait a random amount of time before a reward is available).

I originally found the article on Behavioral Game Design in an article on Cracked.com (5 Creepy Ways Video Games Are Trying to Get You Addicted).  This article captures  much of the sentiment that I came across in a quick Google search: the idea that people are essentially being brainwashed by games which have been inspired by some kind of evil behavioral scientist.  In the end, I don’t think either this view, or that of the Gamasutra feature on Radoff, is entirely accurate.  Behavioral psychology does a wonderful job of describing how our behavior is shaped by the feedback we get from the environment.  These types of effects are happening to us all of the time, mostly without our awareness.  As a game designer, you should take them into consideration.

But, I certainly agree with Radoff that you can’t (or shouldn’t) design a game simply on the basis of the principles of behavioral psychology.  The basic reason is this: all of the best experiments I have ever done with rats would make for terrible, monotonous games.  Any game that used such principles for their only source of inspiration would be a terrible, uninspiring game.

As you may (or may not) know, EfZ is a simple 3D side-scrolling game made using Unity3D, where you play the part of a space adventurer who has crashed on a hostile planet. In the game, you play through a series of 25 stages to battle aliens and ultimately fix your ship and escape.  I teach at Wabash College, EfZ was created as part of my larger research project to study how people learn new behaviors (such as mastering a video game).  As a research project, my goals for EfZ are:

• To get as many people to play the game as we can (to test our research questions).
• To make enough money to offset our development/promotion costs (which are pretty low, about $700 so far).

If the game does well (and brings in more money than its development costs), we would be thrilled, and we will use those funds to continue our research (i.e. to support this project or start a new project).

From an idea to the Nook

As we began development of the game, one of my students (Steven Apostolidis, who did a lot of work on the early versions of EfZ) suggested that we do a mobile release. I thought it was a good idea, as EfZ was going to be a simple game that you could play in stages. So, I bought a copy of the basic Android license from Unity3D while it was on sale and started to look at porting our web beta version of the game to Android. And, I registered at nookdeveloper.

I originally thought of developing EfZ as a long-term project, with an initial release in late 2012.  But, I was drawn in by a promotion that Barnes and Noble started running (I think in October), where apps accepted in November would qualify for special promotions in early 2012. So, during our college’s Thanksgiving break, I pulled a late night and an all-nighter to get a version of EfZ that I could submit. After a couple of rounds of submission, the game was accepted for the Nook Color (but not the Tablet) on 11/22, and went live on 12/1.  Sales from December are shown below.

Sales on the Nook Color/Tablet for December

The numbers

The first version (v1.0.0) sold 12 copies its first day, and 13 on its second day of sales. After that (as you can see in the graph above), sales slid to around 2-4 sales a day for most of the month.  After version 1.2 went live on 12/23 (which added support for the Nook Tablet) sales picked up for the holiday season.  I would guess that the burst of sales around Christmas is a combination of adding support for the Nook Tablet and a flurry of holiday sales of Nook Colors/Tablets.  At the end of December, we had a total of 215 installs (which gives us sales of $148.35).

So, what should we make of these sales?  If I were trying to make a living off of one game, the revenue coming in from EfZ would not be enough to get by.  However, I consider the game to be doing well after its first month, considering that 1) our only marketing was some tweets, forum posts and facebook messages, and 2) which we put together for under $1k.

And, let me point out that our sales numbers put us near the bottom of the Arcade Games category for the Nook: so I reason that there are a lot of people who are making considerably more money than we have.  For developers who are interested, it seems like now is a great time to bring your app to the Nook.  From what I’ve seen on user forums, the Nook users are hungry for more apps to put on their new Colors and Tablets.  I have heard that developers have had some glitches in getting their apps approved and online (and we had some as well, which I may go into in another post), but I think it was worth the effort for us.  I do feel, though, that EfZ is not doing as well as it could on the Nook. For example, other games released at about the same time (like Hamsteria, which I believe is another game made in Unity, or the Annoying Pig Game) have had much stronger sales than EfZ.

Originally, I had thought that doing an exclusive release of our game on the Nook would be a great idea, but now I wonder if the lack of visibility (outside of Barnes and Noble) has hurt us.  While $0.99 is not a lot to spend, I imagine people could be hesitant to spend the money without some confidence that they knew what the game was about.  If we had released the game on the Android Market first, we would have had at least a chance of getting a review or some other type of internet “footprint” that might have encouraged Nook owners to check out the game.  Now, as we’ve drifted out of the “New releases” page, it seems we’ve gotten stuck at our current position on the charts.

If the sales continue at close to their current pace, then I think we will make back our money. But, will EfZ have succeeded as a research project? Remember that our most important goal for EfZ is to study how people learn. If I were testing this game at my college, a sample of 215 people would be phenomenal. However, of the 215 people who bought a copy of EfZ in December, relatively few (less than 20%) have finished more than the first couple of stages (out of 25).  It is likely that our yield (in terms of useful data) is very low so far.

What’s next for Escape from Zargnon?

Given these data (the number of sales, and how far each player goes in the game), we’re looking for ways to promote EfZ on the Nook (Barnes and Noble plans to do some promotions in 2012, but we’re also looking at what we can do on our own). And, we’re rolling EfZ out to other Android devices (and we are focusing on the Android Market, Amazon Appstore, GetJar, Mobango and AppsLib right now).

As we move to places like the Android Market, we’re splitting EfZ into two versions: a full version (like the one available on the Nook) and a trial/lite version with ads (which we are calling Chapter One).

As we were thinking of free vs paid options, one thing we wanted to avoid was having the full version of EfZ available for different prices on different devices.   As a user, I personally find it annoying to buy an app for 1.99 on one device and realize I could have gotten the same app (even if it is with ads) for free on another device.  So, we’re keeping the full version of EfZ at $0.99 (though we may use sales on some platforms/devices as incentives).  In EfZ: Chapter One, users will get the first five stages of EfZ for free (with ads).  We think this will work well, as the first five stages tell one complete story about your journey on Zargnon, and would probably take the typical user a total of 1-2 hours to complete.

Our main reason for making the lite version was that the other Android app stores (like the Android Market) are much more saturated with apps than Barnes and Noble, so it will be even harder to get noticed there. And, many users on the Nook don’t appear to play past the first few levels, so it’s likely that many of the people who bought the full version end up not being very interested in the game. We don’t want people to feel they have wasted their money, and a lite version lets us people try the game out, and targets the full version of EfZ to those people who enjoy it, and want to finish the adventure.  The use of a trial version will hopefully encourage more people to try the game, and when people buy it, they will already know that they enjoy the game.

We want to add a similar trial version for the Nook, but currently Barnes and Noble does not allow in-game ads, so we have no way to monetize the free version.  And, right now Nook users cannot search for just apps that have free trials (so the trial doesn’t really work in the way we need it to: to attract people to try the game out).

Try Escape from Zargnon for yourself:

Currently, the full version of EfZ is out on the Android Market. And, EfZ: Chapter One is out on the Android Market, GetJar and Mobango.  And, you can get the original, full version of EfZ at Barnes and Noble.

https://market.android.com/details?id=com.behaviorgames.EfZ

And, we’ve included a free (ad-supported) version that we are calling Chapter One:

https://market.android.com/details?id=com.behaviorgames.EfZch1

Chapter One includes the first level (the first five stages) and banner ads.  More details will follow, but check them out if you have a chance!

[Update]  We heard back from the Nook developer team, and it sounds like the update will go live next Tuesday (12/20).  So, Tablet owners will have to wait until next week, and we’re sorry for the delay!  In the meantime, Nook Color owners, have you escaped yet?

[Update - 12/21] It looks like the new version is going live (we were able to update our version on a Nook Color).  But, the app is not listed for the Nook Tablet online.  We’re looking into the issue, to make sure that the EfZ update will roll out to the Tablet as well.

Stay tuned: we expect version 1.2 will be ready soon.

[Edit] Well, we made our Friday deadline (just barely!).  After extensive testing, version 1.2 was submitted to B&N at about 11:20PM local time (Eastern in the US).   We did find several additional problems, so we were happy to put in the time.  Now, we’ll keep our fingers crossed that the update passes review.  Stay tuned….

[Update] We’re still waiting for version 1.2.0 to come out on barnesandnoble.com.  It was accepted on Tuesday, and is waiting for publication.  A bunch of new apps came out this morning, so hopefully the good folks at nookdeveloper.com will throw in our update as well!