Tools for developing Android Games: The Slides

The session of yesterday co-organized by and the Dutch Android User Group was a great success. We had over 20 people showing there, many of them told me that it was interesting and fun, and they also learned new stuff, so mission accomplished!

During the Hackaton we had quite some game ideas that were developed to a certain extent (we only had 5 hours). These projects even did a demo at the end:

  • A fast paced 2D scrolling combining tilting controls and jumping. We had a demo with the basic gameplay.
  • A Space flight simulator in 3D using the free NASA 3D models. We saw it working with touch, control it with the sensors was the next step.
  • 3D pong, it was almost working, all the scenery was there and displayed and the ball was moving.
  • 2D Real time strategy. They had the tiled map working and all the game logic implemented (but not displayed). They promised to finish it by next week.
  • 2D Billiard with fling controls. Almost completed, you had to hit the other 2 balls with yours, they you get the point.
And, as the title for the post says, here are the slides:

Latest talks: Microsoft GeekNight & Delft University

Over the past months I have given some talks. The last ones have been at Microsoft TechDays and Delf University. Very different environment and public.

On February 15th there were the Microsoft TechDays. There  I presented “The importance of Visibility” during the GeekNight. I am going to update that talk soon with the latest results from SpaceCat (and the levels of being featured) and probably change the title to “Fly or Die: App Visibility”

And on March 20th I have spoken at Delft University as part of the App Symposium presenting “The Road to Publishing”, trying to motivate students to build their own product.

And of course, this Saturday there is the Tools for developing Android Games.

Photo by Erik Romijn

Featured Levels on Android Market

I stated many times (like in this slides) that between being featured or not on Android Market (now Google Play) means to Fly or Die.

Previously, there were 2 levels of featured; each week new titles ware added and the oldest ones ware shifted out. First you were into the top list -appearing on the header- and into the featured list, that was sorted at random. After the first week you were pushed out of the top, and after one month you were pushed out also from the featured list. It looked like this when Chalk Ball was featured past year:

This changed with the update of Android Market that presents the apps as “tiles”. Now there is a main screen, then another one for most of the categories and, in the case of games, there is another one for the genre. After that you still can browse the normal lists. It looks like this now that SpaceCat is featured:

While I believe that Android Market has too many screens and lists to the point that is confusing to the users and many of these screens are too many clicks and swipes away that they are barely reached, that is not the topic of this post.

Today I want to talk about the stages in being featured inherent to this hierarchical structure. It goes from more to less. I have classified them according to Dragon Ball Saiyan states, to emphasize the power gap.

Featured in Home Screen: Super Saiyan 3

When new featured titles appear, they are usually put on the big banner of the web and also the main screen of the app. This is the first screen users see when they open the market and -I suspect- it has a huge impact.

Needless to say, when you are featured on the home page, you are also featured in the category and subcategories and you appear in the Staff Picks list.

Unfortunately I can’t give you figures about this because SpaceCat was featured directly under Games, but feel free to extrapolate the results from the other cases.

Featured in Category: Super Saiyan 2

This is the screen when users go to find something specific. Fortunately for us Games has an entry from the homepage and it is one of the most visited screens of all the market. SpaceCat was placed there for around 2 weeks, sometimes as a big banner, sometimes as a small one.

Being there we averaged 50k downloads per day. Mind you, SpaceCat is a Free to Play game, a paid app will have a lot less downloads -as we experienced with Chalk Ball-. Still, 50K downloads a day is totally massive. To put it in context SpaceCat had 50K downloads in total from the previous 6 months, including more than 10 blogs reviews, so yes: WOW.

Of course, during this time you are also listed on the subcategory and in the Staff Picks, which just adds to the number of downloads.

Once you had your time here, it is time for some fresh meat, so you will logically be pushed to be only in your subcategory and the staff picks list.

Featured in Subcategory: Super Saiyan Full Power

During this period we averaged 15k downloads a day. That is half what we got per day when Rabbit and Eggs (an Easter themed free game) was featured on the Main Page during Easter 2011.

The number of Android devices out there has grown a lot over the past year. With the figures of past Easter and now I can say that the number of potential users definitely has grown in the same proportion.

Then, after the standard month period, your app will be removed from the Staff Picks list, but will remain on the subcategory for a while longer. Thankfully there are more spots now on Android Market and you are not pushed completely out at that moment.

Featured in Subcategory: Super Saiyan

This was a bit surprising bit for me. When the app was pushed out of the Staff Picks, but still on the subcategory, we observed a drop to “just” 5k daily installs. I was expecting the importance of Staff Picks and subcategory to be the opposite.

Although that is just 10% of what we got on the first stage, it means a lot of downloads and as an indie developer I appreciate this slow decrease in popularity and downloads instead of the sharp drop we experienced a year ago with Chalk Ball.

Although 5k downloads a day sounds small when you come from being on the top, it is still a very good amount of downloads you are very unlikely to get from any other place.

Note: Platty Soft is the current company responsible for the games of The Pill Tree.

Guru Session: Tools for Android Game Development

On March 24th, I will be giving a guru session at Mediamatic Bank (Amsterdam) about tools to build games for Android. This session is organized partly by Appsterdam and partly by the Dutch Android User Group, that’s why we have half of the seats on the Appsterdam meetup page and the other half in the DutchAUG page

There are a few spots left, and I believe it is going to be an interesting one, so go and get one!

I will publish the slides on this blog once the session is done.


When thinking about building a game for Android, one can write it from scratch. Or you can look for tools, libraries and engines that already exist so you don’t have to reinvent the wheel.

We did that at The Pill Tree for both Chalk Ball and Space Cat, both games have different requirements and the solutions we found were also different. In this session I will summarize the strong and weak points of AndEngine and jPCT-AE and the uses you can make of them.
I will also give a brief explanation of other libraries that are interesting, such as ScoreLoop / OpenFeint for scores and awards and give a short introduction to virtual currency and incentivated ads.
After the talk, I will provide the people with the samples of both engines and we will play around with them.