New Android Newsletter: WeeklyAndroid.com

A group of avid Android’ers got together in Vienna and realized that a common theme among the gripes of Android fans was the difficulty of navigating the Android market scene and keeping up with new things.

We thought about this for a while, and today we launched Weekly Android, a newsletter for Android users interested in a weeks worth of news from the Android scene. We will provide a summary every Wednesday, and hope to keep up with the weekly pace! Sign up and enjoy :)

With lots of new things in development, including up-coming new games and updates of old favourites (iconic memory), we’re going to be pretty busy with Android development projects too, so if you hear of anything, or have something to say about Android, let us know!

First issue (August 18, 2010):

Case study: Adding Flock Multiplayer to an Android Game

Since the private beta launch in early June, developers have published the first games on the Android market using the Flock multiplayer engine. In this post we take a look at SpWebGames’ “Othello/Reversi” game, which enabled multiplayer with Flock in a recent update.

Othello/Reversi is an ad-supported, turn-based board game which originally supported single-player and two-players-on-one-phone game modes. A perfect game to extend with multiplayer functionality. Flock is an event based multiplayer framework which can be integrated by adding one jar file to the project source, and which sends events to the Activity after calling FlockEngine.connect().

After releasing the update on the Android market, users immediately started connecting to the servers. The daily connections saw a sharp rise over the first days, quickly stabilizing afterwards. The following chart portrays the number of connections during the first two weeks:

Currently the Othello/Reversi gameserver handles an average of 1,400 connections per day, with the players spending a total of 82 game-hours online every day. 

The following screenshot shows more detailed statistics taken from a random day (time is in UTC). The interface includes a real-time ticker with the number of currently online users, and hourly overviews of connections, games played and the time users spent online.

The green bars represent total connections during an hour, the yellow bars just those which found an opponent (some players quit before a matching opponent is found). On average 75% of the Othello/Reversi players find opponents within the first 10 seconds.

After the release of the multiplayer update “Othello/Reversi” saw an increase in the advertisement revenue of about 30%.

We will follow the development of the numbers over the next few months as more and more users start playing online, with a follow-up post coming in mid-July.

• SpWebGames
• Othello/Reversi (Cyrket)

About: Flock Multiplayer Engine is a start-up in beta, and offers two months free usage of a private gameserver without any obligations. If you are interested in adding multiplayer to an Android game, create an account and have a look at the SDK, examples and documentation.

Elo Rating Calculation for Games (from Chess)

Recently I’ve implemented a rating system for an Android game and found the Elo rating system from chess to be a very good fit and easy to implement. The idea of the ELO system is to increase or reduce points proportional to the strength difference of the players. A player with more points is expected to win, thus if he only reaches a draw will loose points and the weaker player will gain some.

For the examples we use a K factor of 32, which is used by FIDE for rating beginners (a lower K factor is used for masters and will reduce the number of points won/lost).

This is the algorithm implemented in Java for calculating the ratings:

// Returns an array of two doubles: [0] is the new rating for player A, [1] for player B
//
// Parameters:
//   status: 0 = draw, 1 = player A won, 2 = player B won
//   RA, RB: the players points before the game
private double[] calcElo(int status, double RA, double RB) {
	double QA = Math.pow(10, RA/400);
	double QB = Math.pow(10, RB/400);

	// set the desired k factor
	double k = 32;

	double EA = QA / (QA + QB);
	double EB = QB / (QA + QB);	    	

	double SA = 0.5; // draw
	double SB = 0.5; // draw
	if (status == 1) {
		SA = 1;
		SB = 0;
	} else if (status == 2) {
		SA = 0;
		SB = 1;
	}

	double[] res = new double[2];
	res[0] = RA + (k * (SA - EA));
	res[1] = RB + (k * (SB - EB));
	return res;
}

DMCA notice — “Connect 4 Online” now “Four Online”

About two months ago, the company “Hasbro” sent Google a DMCA takedown notice about our games “Connect 4 Online” and “Don’t Connect Four“. Hasbro apparently owns the trademarks of the terms “connect four” or “connect 4″ (beside more than 4.000 other terms).

Our two games have been suspended from the Android market, which is especially painful because of the good ratings and the long process to get into the upper spots in the “popular games” listing.

It was not possible to edit the information of the suspended projects in the market website. All I could do was sending a mail to the generic Google address which sent me the DMCA notice, with the question if I could update the game with another name and sent them the .apk file. I (surprisingly) got a response, but telling me I would need to submit it as a new project.

I’ve submitted the game again as “Four Online“, available in “Games -> Brain&Puzzle”. If you happen to have the original “Connect 4 Online” installed, you’ll need to remove it in order for “Four Online” to work.

I hope you enjoy the game and maybe it will (again) climb up to a good spot in the popular games listing. If you have any feedback or experience issues, please let me know!

P.S.: Be sure to check about trademarks before you release your next project! ;-)

New Categories in Android Market: Comics, Health, Sports, Themes

As announced earlier this month in the android developers blog, Android Market got four new Categories for Applications: Comics, Health, Sports, Themes.

left to right: Application Categories; Comics; Health

Many of us expected this to happen with the next Android update to version 1.6, which also includes a white Theme for the Market.

Each of the new categories currently contains about 50 apps. I expect the list to grow rapidly; due to the small amount of applications new apps are a lot more visible to users, and now it would be easier than anytime later to secure a top spot in the “by popularity” listings.

The next update of MyMarket (planned for today (Wednesday) or tomorrow) will also include the new categories.

A sneak peek at ADC2 submissions (Updated)

A thread at the “Android Developers” Google Group about ADC2 submissions keeps growing, with interesting background stories of many participating teams. Here is the current list of mentioned apps and games and their respective categories (last update @ 22:30 gmt):

If you know about other submissions, let me know as I try to keep the list updated.

ADC2 Submissions Thread (Update 2)

The Android Developer Challenge submission deadline was reached yesterday midnight, and now a lot of Android developers are curious what’s going on, which apps were submitted and how many submissions there were in total.

Unfortunately Google seems to dismiss the opportunity to create more emotions and buzz inside the Android community, for example by a quick blog post about the status quo and further progress. The latest blog on the android developer blog is “ADC2 Submissions Closing Monday!”, and the ADC2 homepage still says “Submit your app today!”.

Nevertheless there is a interesting thread being started over at the Android Developers Google group with the title “Hmm… at last ADC2 is out of our way … tell about your app and experience“. Quite a few developers which submitted to the ADC2 posted about their projects with a bit of background to each. It’s very interesting to read, especially since new posts are coming in all couple of minutes. I’d suggest you guys head over there and give it a heads-up about your projects if you’ve submitted any!
Read the rest of this entry »

MyMarket v1.0 (submitted to the ADC2)

• US & EU market results (changeable in the settings)
• "Recommended" listing displays the number of user-votes
• Faster update of "My Downloads"
• In My Downloads, items with updates are listed on top
• Screen rotation works with filters, search, etc.
• Autocomplete for the search box (with last 10 searched)
• Quickfilter: When browsing the apps or games list and adding a new filter, the last clicked items title/dev-name are suggested in the keyword textview (as autocomplete)
• Last used tabs are remembered everywhere
• Scrolling really far down works smoothly
• Various minor bugfixes and improvements

left to right: Recommended (with votes), Detail & comments preview, Settings

left to right: Listing, Filters, Autocomplete