I have released a simple casual game on the Android Market. I decided to make a quick game while between jobs to see how the market has changed since I released my last game about a year ago. I decided to dust off a 2D OpenGL ES engine I wrote about a year and a half ago. It also uses custom Box2d JNI bindings and the Android NDK for physics. I have also integrated the new Android LVL licensing system, OpenFeint leader boards and achievements, and obfuscation using Proguard. It is designed specifically for hdpi devices and I am excited to see how it works on some of the upcoming Android tablets.

One snag I hit was when obfuscating with Proguard and having classes with JNI methods, these classes need to be “kept” by the proguard config file so that the method names and package still match the JNI headers and native source compiled by the NDK:

-keep class com.awalkingcity.casual2d.box2d.Box2DContext {;}

Another thing I am attempting to do is limit which devices can see the app in the market. The app was designed for HDPI screens as well as devices with faster processors than some of the first generation Android devices. Limiting by screen size does not work because the phones I am trying to target report both Medium and Large. So what I tried doing was adding “uses-feature” android:glEsVersion=”0×00020000″. My reasoning is that faster hdpi devices support OpenGL ES 2.0 while slower devices do not. I am not sure whether some of the custom ROMs out there hack OpenGL ES 2.0 support into the older devices or at least spoof support for it.

I am going to update this post with a couple of more tips and tricks I encountered while developing this game.

Here is the market description and some screen shots:

Monkey Fill is a simple and addicting physics game!

The goal is to fill the screen with monkeys while avoiding the bouncing green balls.

Hold down and drag your finger to grow monkeys.They will stop growing if they touch another monkey or pop if they hit a ball.

After one day of being on sale it became very obvious a free version is needed to drive sales of the full version, so I created a limited free version, we will see how well it does in the sea of free apps in the market.

Here is the OpenFeint listing: Monkey Fill