Every indie developer eventually faces the cross-platform question. Your game runs beautifully on your development machine. Now how do you get it onto phones, consoles, and handheld devices without rewriting half the codebase?

The good news for 2D developers: sprite-based games are inherently more portable than 3D titles. The rendering requirements are simpler, the input models are more adaptable, and the performance headroom is larger. But “more portable” doesn’t mean “portable for free.” Cross-platform 2D development still requires deliberate architectural decisions, and the earlier you make them, the less painful the process becomes.

Architecture First

The single most impactful decision for cross-platform development happens before you write gameplay code: how you separate platform-dependent code from platform-independent code.

The Abstraction Layer Pattern

Build thin abstraction layers for platform-specific functionality:

Game Logic (pure, platform-independent)
    │
    ├── Renderer Interface
    │   ├── PC / OpenGL implementation
    │   ├── Mobile / OpenGL ES implementation  
    │   └── Console-specific implementation
    │
    ├── Input Interface
    │   ├── Keyboard + Mouse
    │   ├── Touch
    │   └── Gamepad
    │
    ├── Audio Interface
    │   ├── Desktop audio backend
    │   └── Mobile audio backend
    │
    └── Storage Interface
        ├── Desktop filesystem
        ├── Mobile sandboxed storage
        └── Console save system

The game logic — all your gameplay code, AI, physics, level loading — should never directly call platform APIs. It talks to interfaces, and platform-specific implementations of those interfaces handle the details.

Engines like HGE already provide some of this abstraction. The system state management and rendering APIs abstract away many platform details, though you’ll still need additional abstraction for mobile-specific concerns.

Resolution Independence

Design your rendering pipeline to be resolution-independent from the start:

  • Use a virtual coordinate system for game logic (e.g., 1920×1080 logical units)
  • Scale and letterbox to fit actual screen dimensions
  • Keep UI separate from game rendering so it can adapt to different aspect ratios
  • Test at multiple resolutions early — phones range from 720p to beyond 1440p

Platform-Specific Concerns

PC (Windows, Linux, macOS)

The most flexible platform with the fewest constraints:

  • Input: Keyboard + mouse primary, gamepad optional but increasingly expected
  • Performance: Generally abundant; focus on consistent frame timing rather than raw throughput
  • Distribution: Steam, itch.io, direct download
  • Testing: Easiest to iterate on, widest range of hardware configurations

Mobile (iOS, Android)

The most constrained platform in terms of input and power:

  • Input: Touch-only for most players; some use controllers but don’t require them
  • Performance: Thermal throttling is a real concern; target consistent 30fps rather than inconsistent 60fps
  • Battery: Profile power consumption, not just frame time
  • Memory: Mobile devices kill background apps aggressively; save state frequently
  • App Store guidelines: Review processes, content restrictions, and monetisation rules vary

Console

The most controlled platform with the highest quality bar:

  • Certification: Console manufacturers require specific features (achievements, controller disconnect handling, save data management) and will reject submissions that don’t meet requirements
  • Input: Gamepad only; every feature must be accessible via controller
  • Performance: Fixed hardware means you can optimise precisely, but also means you can’t rely on “players will have better hardware”
  • Development kits: Require application and approval; not all indie developers qualify

Input Design for Cross-Platform

Input is where cross-platform design gets genuinely difficult. The same game needs to feel responsive whether the player is using a keyboard, a touchscreen, or a gamepad.

Design for the Most Constrained Input First

Start with gamepad or touch, then add keyboard/mouse refinements. This guarantees that every interaction works with limited input, and keyboard users get a bonus rather than touch users getting a compromise.

Touch-Specific Adaptations

For 2D games on touch devices:

  • Virtual buttons work for simple controls but feel terrible for complex input
  • Gesture-based controls (swipe, drag, tap zones) often feel more native
  • Auto-aim and generous hit detection compensate for imprecise touch
  • Larger interactive elements — minimum 44pt touch targets for UI

Input Configuration

Let players remap controls on every platform. This is a quality-of-life feature that costs relatively little development time and significantly improves accessibility.

Asset Management

Resolution Variants

Ship multiple asset resolutions and load the appropriate set at startup:

  • @1x: Mobile phones, low-res displays
  • @2x: Tablets, HD displays, most PCs
  • @4x: 4K displays (optional; @2x upscaled often looks fine for pixel art)

Texture Atlasing

Pack sprites into texture atlases per platform. Mobile GPUs have different optimal atlas sizes than desktop GPUs, and the batching benefits vary. The HGE sprite system provides efficient batching on desktop; mobile platforms need equivalent optimisation.

Audio Formats

Different platforms prefer different audio formats for memory and decoding efficiency. Abstract your audio loading to select the appropriate format at runtime.

Testing Strategy

The Testing Matrix Problem

With N platforms × M device configurations × P input methods, exhaustive testing is impossible. Be strategic:

  1. Tier 1: Your primary platform — test everything here
  2. Tier 2: One representative device per additional platform — test core gameplay and critical paths
  3. Tier 3: Edge case devices — test via community beta

Automated Testing

Invest in automated gameplay tests that can run headlessly on any platform. Simulate input sequences, verify game state, and catch regressions without manual play sessions.

Community Betas

For platforms you can’t test extensively in-house, structured beta programs with clear feedback channels are invaluable. The community forum approach works well for gathering platform-specific feedback.

Build Pipeline

Unified Build System

Use a build system that can target all platforms from a single codebase:

  • CMake for C/C++ projects across PC, mobile, and console
  • Platform-specific build scripts that invoke the shared build with the right flags
  • CI/CD that builds all platform targets on every commit

Configuration Management

Platform differences should be handled through configuration, not code branches:

config/
├── pc.json
├── mobile.json
└── console.json

Each config specifies resolution defaults, input mappings, audio quality settings, and platform-specific features.

For a small team building a 2D game with cross-platform aspirations:

  1. Start on PC — fastest iteration, easiest debugging
  2. Build abstraction layers from day one — even if you’re only targeting PC initially
  3. Add mobile second — it forces the most design adaptations
  4. Add console last — it requires dev kits and certification knowledge
  5. Use your framework’s strengths — HGE’s rendering and input handling give you a solid PC foundation to build from

The key insight: cross-platform isn’t about doing more work. It’s about doing the right work once, with the right architecture, so each additional platform is an incremental effort rather than a rewrite.

Check our projects page to see cross-platform thinking in practice, or explore the HGE engine documentation for a look at how abstraction works in a real 2D framework.