This is a collection of thoughts and tips when developing Flash games targeted to a mobile, more specifically to Android using Adobe’s AIR . I write these notes with a specific focus on full screen games. I’ll cover a few things to think about when designing your game, and a then a few tips and tricks to keep in mind that will [hopefully] save you finding out the hard way.
Planning for Mobile
Before you start making a game for mobile there are some important things to consider, which will save a lot of time and stress if you plan for them.
Type of Gameplay
The type of games typically played are very short bursts of gameplay – while traveling, sitting on the toilet, watching TV. Gameplay that can be stopped and started very quickly. Short bursts of gameplay are very typical of the mobile platform and your games should be made to work with this.
A couple of your options are:
- make your games levels short and sweet, saving the players progress as they complete stages
- make the game save it’s state so that it can be stopped quickly and continued at a later time very easily
- make a game that is only about the score from a single session of play, save that score as soon as it’s achieved
I recommend you keep your games very simple (though still fun) at first, until you get the hang of publishing for this platform and finding out it’s pitfalls. It’s better to get content out there and learn from your mistakes than embark on a huge project and make costly mistakes.
With mobile phones mostly having touch screens, and a few phones having very small keyboards it’s important to make your game very easy and simple to control. Typically there is no mouse, no arrow keys (or space bar) and screen sizes can be a factor in how much you can fit on a screen at once.
The best option is to choose an intuitive control method, that perhaps adapts to the gameplay. For example, with a vertical scrolling space shooter game you could make the players ship constantly fire bullets with the player simply steering the ship around with their finger, and for a powerful shot the player could double tap their ship. It also pays to remember that fingers get in the way of the screen, so your gameplay should allow for rather large obstructions (for example: my hands are much bigger than my wife’s). If you have a character or ship that the character controls, consider positioning them above where the players touch point will be so that it is still visible during play.
One of the downsides of the need for such large buttons (and fingers blocking the view) is that your gameplay area gets greatly reduced. Consider this when designing your gameplay! If a game is frustrating to see while playing, your game will be quickly become ignored.
Finger controls on mobile screens can also be fairly inaccurate, sometimes not quite registering touches or finger presses accurately, and this varies quite a lot from phone to phone. The best option is to simplify controls and allow for players not always being able to accurately touch the screen. A simple way to deal with this is to make hit spots larger, or take the average values of input (depending on the gameplay).
Give the player a clear and easy way to quit your game. I have received several frustrated comments about this. Players need a large button labeled ‘exit’ or ‘quit’. Don’t make it hard for them to find. If they like your game, they will be back.
Note: You don’t have to use “TouchEvents” to capture a player’s input, traditional mouse events work fine. In fact, I haven’t used TouchEvents in any games I’ve made.
Screen aspect ratio
Modern phones introduce an interesting difference to traditional web based games. Online game resolution varies widely, depending on the developers preference. With the current range of mobile phones we pretty much have a standardised format – depending on whether your content is horizontal or vertical we now have wide screen (or very tall) proportions that take up the entire screen.
There is a rapidly growing number of Android phones, each with slight differences in proportions. Do a little research into the main phones you will be targeting and establish a format that works for as many as you can. If you don’t use up the entire screen your game can look unpolished or poorly adapted. Make sure your background images bleed enough off-screen to cover such slight differences in size, or smartly design your content to look good even if there is extra space around the edges.
An added benefit of using the full screen is that your games don’t have to compete with with the surrounding webpage elements, allowing you to create a much more engrossing experience.