Creating a complex game on Android from scratch

The development of AAA mobile applications has ceased to be the prerogative of large studios with million-dollar budgets. Modern tools allow independent developers to create high-performance projects directly on a computer or even a tablet. However, the path from an idea to a finished APK file that can hold the player's attention is strewn with technical obstacles.

Creating a complex game requires a deep understanding of the Android architecture, the features of working with memory and the graphics pipeline. You not only have to write code, but also optimize it for thousands of different device configurations. In this article, we will look at the key stages of production, from the selection game engine to the final assembly of the build.

Are you ready to dive into the world of low-level optimization and complex logic? The process will require patience, but the result in the form of a working application in the Google Play store is worth it. Let's start with the foundation, without which any building will collapse.

Choosing a technology stack and engine

The first decision that will determine the fate of your project is the choice of development tool. To create of a complex game native development in Java or Kotlin often turns out to be ineffective due to the lack of ready-made solutions for physics and rendering. It is much wiser to use specialized frameworks.

The market leader remains Unity, offering a balance between performance and usability. This engine supports the language C# and allows you to export projects for any platform with minimal code changes. An alternative is Unreal Engine, which is ideal for projects with photorealistic graphics using the C++ language or the Blueprints visual programming system.

If your goal is 2D projects with a unique style, you should take a closer look at Godot. This engine is completely free, open source and uses its own GDScript language, syntactically similar to Python. It consumes less system resources during development, which is critical for weak computers.

⚠️ Attention: Licensed engine conventions may change. Unity, for example, has implemented setup fees after reaching a certain revenue threshold. Always check the latest terms of use on official websites before starting a commercial project.

The choice of stack also depends on the team. For a solo developer, the speed of prototyping that Unity provides is important. For a team of programmers accustomed to strong typing and memory control, Unreal Engine may be a better option. Do not forget that changing the engine in the middle of development is almost a complete restart of the project.

Project architecture and design patterns

A complex game differs from a simple one not only in graphics, but also in the structure of the code. Chaotic scripting without a system will quickly turn the project into "spaghetti code" that is impossible to maintain. The use of architectural patterns such as MVC (Model-View-Controller) or ECS (Entity-Component-System) is a mandatory requirement.

The ECS pattern is especially popular in modern development of high-load systems. It allows you to separate data (components) and logic (systems), making it much easier to manage thousands of objects in a scene at the same time. B Unity The implementation of DOTS (Data-Oriented Technology Stack) is based on this approach.

It is important to think about the event system. Direct references between objects create rigid dependencies that complicate testing. Instead, implement a system events or signals, where objects communicate through an intermediary without knowing each other's existence. This will make the code modular and flexible.

Don't forget about managing game states. Menu, pause, gameplay, loading screen - all these are separate states, the transition between which must be clearly regulated. Using the pattern State Machine will help avoid bugs when the game “freezes” between the menu and the level.

Working with graphics and optimizing rendering

Mobile devices have serious limitations on heat generation and energy consumption. What works on a PC can overheat a smartphone in five minutes. Graphics optimization is not the last step, but a process that accompanies development from day one. The key indicator here is the number Draw Calls (draw calls).

To reduce the CPU load, use the batching technique. It combines objects with the same materials into a single draw call. Static batching is suitable for stationary objects in the environment, and dynamic batching is suitable for moving characters. However, excessive use of dynamic batching can increase memory consumption.

Optimization technique	Impact on CPU	Impact on GPU	Difficulty of implementation
Static Batching	Strong reduction	Neutral	Low
LOD (Level of Detail)	Average decline	Strong decline	Average
Occlusion Culling	Strong decline	Strong reduction	High
Texture Atlas	Medium reduction	Neutral	Low

Textures are another resource that needs to be saved. Use texture atlases to combine many small images into one large image. This reduces the number of times the video card switches textures. For mobile devices, the compression format ASTC is the de facto standard, providing better quality with a smaller file size compared to the legacy ETC2.

What is Occlusion Culling?

This is a technology that prevents objects from being drawn that are obscured by other objects from the camera. For example, if the player is standing with his back to the wall, the engine will not waste resources on drawing furniture in the next room. Enabling this feature in the engine settings can increase FPS by 20-30% in dense scenes.

The Level of Detail (LOD) system automatically replaces complex models with simplified versions as they move away from the camera. Setting distance thresholds for LOD requires careful testing on real devices to avoid a noticeable “jump” in picture quality during the game.

Implementation of game physics and logic

Physics in mobile games should be not only realistic, but also predictable. Using built-in physics engines, such as Unity or Unreal, simplifies the task, but requires proper configuration. Incorrect collider settings can cause a character to fall through the floor or get stuck in a wall. PhysX in Unity or Chaos in Unreal, simplifies the task, but requires proper configuration. Incorrect collider settings can cause your character to fall through the floor or get stuck in a wall.

For complex interaction logic, avoid using physical colliders where simple mathematical distance checks (Raycasting) will suffice. The physics engine is a heavy resource. If you just need to check if the player has pressed a button or if an item is in range, use triggers or vector math.

⚠️ Warning: Avoid creating physical objects (Rigidbody) inside the Update loop. This leads to sharp drops in frame rate. Create a pool of objects in advance and activate them as needed.

Synchronizing physics with the screen refresh rate is a separate problem. On devices with variable refresh rates (60 to 144 Hz), physics may behave differently. Fix the time step (Fixed Timestep) in the project settings so that the simulation works equally stably on all smartphones, regardless of screen power.

Input control and adaptation to screens

The world of Android devices fragmented not only in terms of hardware, but also in terms of screen sizes. From compact phones to huge tablets, your game should look good everywhere. The use of canvases with scaling mode Scale With Screen Size is a basic requirement for interfaces.

Input processing must be abstracted from a specific device. The player can use the touch screen, gamepad, or even the keyboard. Create a single input manager that translates different signals into the same game actions. In Unity the new system is perfect for this. Input System.

Do not forget about the “safe areas” (Safe Area). Modern smartphones have camera cutouts and rounded corners. The interface should not be overlapped by these elements. Receive safe zone data programmatically and dynamically adjust controls to it.

Multi-touch is a standard for mobile games. Make sure your input system supports multi-finger tapping. This is critical for shooters where you need to run, shoot and move the camera at the same time. Test scenarios where fingers overlap each other on the screen.

Testing, Debugging and Publishing

The final stage is turning the project into a finished product. Assembling the release version (Build) requires the correct configuration of the Signing Key. Never lose your Keystore file, as without it you will not be able to update your Google Play app in the future. This is an ironclad rule.

For debugging, use profiling tools. Unity Profiler or Unreal Insights will show performance bottlenecks: CPU overload, memory leaks or rendering problems. You need to test the game on real devices, and not just in an emulator, since emulators do not always correctly display the operation of the sensor and battery.

adb logcat -s UnityActivity

This command in the terminal will allow you to display logs of a specific application from the connected device, which is convenient for finding errors that are not visible in the editor. Publishing to Google Play Console requires preparing graphic assets, describing and filling out a content form. The moderation process can take from several days to a week.

⚠️ Attention: Google Play policies have tightened the requirements for data availability (Data Safety). It is your responsibility to specify exactly what data your application collects and how it is used. False information will lead to blocking of the developer's account.

Frequently asked questions (FAQ)

How long does it take to create a complex game alone?

Development time varies greatly and depends on the genre, the experience of the developer and the assets used. A simple prototype can be made in a week, but a full-fledged complex game with balance, graphics and polish usually takes from 6 months to 2 years of work alone.

Do you need to know C++ to develop for Android?

No, it is not necessary. Engines like Unity use C#, and Godot uses GDScript. C++ is required mainly for Unreal Engine or when writing native libraries for specific optimization tasks, but for most tasks high-level languages ​​are sufficient.

How to make money on the game if I’m a beginner?

The most popular monetization models for mobile games: advertising (AdMob, Unity Ads), in-game purchases (IAP) and paid downloads. For beginners, a combination of advertising and small in-game purchases is often the most effective strategy.

Is it possible to create a game entirely on a smartphone?

Technically this is possible using applications like Unity Remote for testing or specialized IDEs on Android, but full-fledged development of a complex project requires PC power to compile code and work with heavy assets.