Move Beyond Virtual Machines: Real Devices Are Key for Reliable Testing

What are Virtual Machines and Virtual Machine Testing?

First coined in the 1960s, "virtualization" refers to creating virtual versions of computing resources like servers, storage devices, even entire data centers. By the late 90s, VMware made it possible to run multiple virtual machine (VM) instances on a single server.

On the testing front, virtual machines power emulators, simulators and related solutions used to mimic target environments. Teams leverage VMs to validate software without needing to procure and maintain every physical device type.

Key VM-based testing tools include:

Emulators: Android Studio‘s emulator virtualizes Android environments for testing and debugging apps. It translates Android‘s ARM instructions into x86 code for the underlying Intel CPU.

Simulators: Solutions like the XCode iOS simulator run the host machine‘s OS while replicating the target platform‘s API frameworks. Apps can be tested as if running natively within iOS.

Hybrid solutions: Some tools combine emulation and simulation for flexibility. HAXM emulates Intel-powered Android devices but renders UI via the fast GPU of the tester‘s machine.

Drivers of VM Testing Adoption

Virtual testing environments gained immense popularity by providing:

• Convenience: Instant access to many device types from a laptop
• Cost efficiency: Avoid scale costs of real device labs
• Scalability: Spin up more VMs as needed to scale test runs

However, despite the gains…

VM Testing Has Not Eliminated the Need for Real Devices

Emulators, simulators and related solutions aim to mimic target devices, but fall short in replicate real-world conditions:

Performance Overhead

The binary translation underpinning emulators often introduces 20-30% performance overhead. Real devices run natively on hardware tuned to their OS and apps.

Failure to Match Physical Device Capabilities

• CPU benchmarks run 30-50% faster in Android Studio than on real devices
• Sensor data can differ by as much as 80% between VMs and hardware
• Network traffic shaping lacks fidelity to real mobile networks

Such gaps lead to inaccurate test results that fail to reveal reproducibility issues that may frustrate users post-deployment.

Resource Constraints

Virtual machines share the compute resources of their underlying host device. This limits configurations to what the host hardware can support. Today‘s phones pack more memory, storage and processing power than many laptops running VMs.

In total, VMs cannot offer the test reliability and confidence teams need to release high-quality digital experiences. Real devices remain critical.

Why Real Devices Remain Vital for Thorough Testing

While simulators and emulators serve key purposes, true confidence comes only from testing on real devices – the actual hardware and software users interact with daily.

Real devices expose software to the full range of hardware variances, performance characteristics, edge cases and defects that can lead to application crashes detected only through real-world usage.

And by leveraging real device cloud solutions, teams gain affordable, on-demand access to vastly more device types than possible via local labs. Scalability barriers vanish.

Top providers have amassed repositories spanning:

• 2,000+ phone and tablet models
• Numerous wearable devices
• 20,000+ browser environments
• An expanding roster of IoT devices

With real mobile and desktop devices, testers can execute additional validation workflows like:

• Automated cross-browser testing at tremendous scale
• Responsive web design inspection across endless device types
• Visual UI testing by comparing screenshots to historical baselines

So while the convenience of virtualization expanded testing possibilities, true confidence demands real devices. The two approaches must mesh together to enable comprehensive validation while balancing budgets.

Conclusion

Virtual machine testing undeniably holds appeal. The ability to spin up devices instantly right from a laptop fueled tremendous time and cost efficiencies.

However, emulators and simulators carry well-known pitfalls that undermine test reliability. Confidence requires real-world validation on real devices – the actual hardware and software platforms used by application and web users worldwide.

By combining virtual machine testing with real device cloud access, teams achieve both convenience and testing thoroughness. This fusion approach brings true reliability while maximizing ROI on infrastructure.

The innovations will continue on both fronts. But for now and the foreseeable future, real devices remain indispensable to releasing flawless digital experiences at scale. Virtualization expanded possibilities; it did not eliminate needs. When reputation and user trust hang in the balance, real devices answer the call.