As a seasoned app tester who has evaluated performance, security and reliability on thousands of iOS devices, I‘m often asked – "Can‘t I just use an iPhone emulator on my computer instead of actual phones?"
It‘s an fair question since maintaining real devices is expensive and emulators are free. But while emulators have some uses, exclusively relying on them risks embarrassing app failures upon launch.
In this comprehensive guide, I‘ll clear up common misconceptions, explain inherent emulator limitations, provide real-world examples of problems they miss, and offer best practices on when to utilize real cloud-based devices for rigorous testing.
A Quick Primer on iPhone Emulators
Let‘s quickly define what an iPhone or iOS emulator actually provides from a technical perspective before examining their pros and cons.
There are two main classes:
Simulators
These are software environments that mimic iPhone hardware and features. Xcode ships with iOS simulators that allow basic prototyping without phones. Third parties also offer simulators, often focused on app demos.
Virtual Devices
Hypervisor-based emulators like CoreLLium and device clouds like BrowserStack can create virtual iPhones with significantly more accuracy in representing hardware and software capabilities closer to the real counterparts.
Comparison of emulator vs real device testing
But even advanced enterprise grade virtual devices cannot perfectly mimic intricately designed Apple hardware and tight OS integration powering the iPhone experience. This is why thorough real device testing is non-negotiable especially as developers rely more on exclusive features across regular and Pro iPhone models.
And that brings us to…
3 Key Reasons Why iPhone Emulators Fail for Robust Testing
While I always recommend starting with emulators during initial dev and debugging, they inevitably fall short when preparing for launch.
1. Inability to accurately test new hardware and sensors
Recent iPhones boast sophisticated cameras, LiDAR sensors for AR, facial recognition via FaceID, motion sensors with fast response times, always listening microphones and specialized neural engine silicon.
Virtual emulators struggle to effectively mimic this dense combination of hardware and software. Any app leveraging these cutting edge iPhone or iPad capabilities requires real device testing.
As an example, I tested a multiplayer AR game that worked flawlessly in simulators during development. But upon testing on real devices, the faster user motions completely broke rendering and gameplay by exposing CPU/GPU constraints that emulators masked.
2. Lack of support for field testing under real-world network conditions
Cellular data speeds vary hugely across locations with most users often connecting via WiFi. Applications need to account for bandwidth fluctuations, signal strength changes and cellular-WiFi hand-offs.
But emulators only operate on the stable office WiFi and ethernet conditions they run on, masking field performance issues. Fostering relationships with mobile carriers to test on current networks across target markets is invaluable.
I will never forget the live video streaming app that always buffered perfectly on the emulator right up to launch day when 40% of users reported failures amidst an OS update modifying network balancing behavior.
3. Inability to catch power and thermal related app problems
New iOS updates also often aim to improve battery life optimizations. But developer code can inadvertently consume excessive energy leading to early shutdowns.
And graphics/computation heavy apps also heat up the device differently. The iPhone then throttles CPU speed to prevent overheating which again virtual emulators cannot accurately simulate.
In closing, virtual emulators or simulated test environments have their place in exploratory phases. But as budgets allow closer to launch, I always recommend complementing with real cloud device testing or in-house physical labs modified for flexibility.
This provides protection against unpleasant data loss, crashes and customer complaints that fully surface only when iPhones operate untethered in field conditions reflecting complex user needs amidst dynamic technology improvements by Apple. I offer tips on constructing a layered test approach below.
Combined emulator and real device testing – best practices
Based on over a decade of test experience across startups to enterprises shipping innovative iOS apps, here is a high level test methodology I advocate:
Combined emulator and real device testing strategy
Emulators
Rapid prototyping during initial builds when code changes rapidly along with some unit test automation suits this phase. I collaborate closely with developers at this stage to understand functionality being coded.
In-house real devices
As core features get coded, I transition testing to the latest iPhones managed internally. Structured exploratory tests focus on functionality while monitoring resource usage. Filing actionable bugs is crucial before filler coding bloats apps.
Crowd-sourced field testing
Releasing betas onto crowd testing platforms lets you gather video evidence from a diverse set of real users on varied devices, in multiple regions, on different carriers. Failures here must be fixed before proceeding.
Cloud real devices
Finally, leveraging on-demand device clouds lets you scale up test parallelization across 20,000+ device models and iOS versions. Automating sophisticated, segmented test suites targeting different markets is key. Percy by BrowserStack also enables advanced visual testing automation.
While thorough testing requires some investment, identifying hard to replicate mobile bugs early saves massive costs down the line. With over a billion iPhone users on the planet and growing, no app developer can afford postponing robust real device testing until post-launch.
Feel free to reach out to collaborate on cost-optimized testing plans for your app specifically. With focused manual testing and automation, we can launch confidently instead of keeping fingers crossed!
