Bridging the Gap: Developing Audio AI Applications Across Android and iOS with Hybrid Processing

How Switchboard helps to build voice AI apps.

Voice AI applications are rapidly emerging, from real time translation to voice assistants and interactive media experiences. However, developing high-quality Voice AI solutions remains challenging due to platform limitations and the shortcomings of current frameworks and tools.

Android's fragmented ecosystem and outdated real time communication (RTC) stack create inconsistencies in performance, making it difficult for AI-driven voice applications to deliver reliable and low-latency interactions. Meanwhile, Apple's tightly controlled environment limits developer flexibility, restricting the ability to customize and optimize AI processing pipelines. Existing solutions like WebRTC, platform-specific APIs, and purely cloud-based approaches fail to resolve these issues fully, leaving developers with suboptimal performance, high latency, and limited adaptability.

Many tradeoffs depend on whether the AI model lives on-device or in the cloud. For example, latency and offline operation favor the former, whereas accuracy and breadth of capabilities favor the latter. While on-device models continue to become more capable, the most advanced models will likely require cloud compute in many use cases. Hence, the future of AI is hybrid. By intelligently balancing local and cloud-based processing, developers can create responsive, high-performance audio applications that work seamlessly online, offline, and across various devices, including those with limited compute and memory available. Therefore, tooling is needed to help build seamless, cross-platform, low-latency audio pipelines with modular, hybrid processing capabilities.

Challenges on Android and iOS

Despite Android's dominance in the mobile market, its fragmented device ecosystem makes it difficult to ensure consistent audio AI performance. With thousands of Android devices featuring different microphones, audio processing chips, and software configurations, developers face unpredictable behavior in AI-driven voice applications. Additionally, Android's reliance on WebRTC for real time audio presents challenges. WebRTC's default acoustic echo cancellation (AECM, AEC3) and voice activity detection (VAD) were not designed for modern AI-driven applications, leading to suboptimal performance. On top of that, the platform's audio stack introduces unpredictable latencies that negatively impact user experience, making real time responsiveness difficult to achieve.

Meanwhile, Apple's ecosystem provides more consistency but introduces other constraints that affect AI-driven audio applications, particularly in adapting AI models to handle real time processing demands efficiently. The company's strict system controls mean that developers have limited access to lower-level audio processing, and while Apple's audio pipeline (VPIO) is highly optimized, it does not allow for easy replacement or modification of key audio components. Furthermore, Apple prioritizes battery efficiency, imposing strict limits on background processing and resource usage, complicating the optimization of real time AI audio applications.

When Purely On-Device or Cloud Processing Falls Short

Given OS limitations on iOS and Android, one might wonder how to develop AI audio apps best. Android's open ecosystem and diverse hardware tend to favor cloud-based solutions, as device constraints often limit the feasibility of high-performance on-device AI. On the other hand, Apple's tightly integrated hardware and software ecosystem offers more robust on-device processing capabilities. Still, its strict system controls make it less flexible. So if you want to develop a mobile application with similar functionality on both platforms, which approach should you take?

There are cases where a purely on-device approach makes sense. When privacy is the top priority, such as in voice-controlled healthcare devices or secure voice authentication, keeping all processing local ensures data never leaves the device. On-device AI also shines in low-latency, always-available applications that must function even without an internet connection. Conversely, cloud-based AI is beneficial when models require immense processing power or access to vast, evolving datasets, such as large-scale transcription services or AI assistants that improve through aggregated learning.

However, both approaches have inherent trade-offs, and neither platform fully supports a single-method approach across all AI use cases. Hardware constraints limit on-device models, while cloud-based solutions suffer from latency, network dependency, and potential privacy concerns. This leaves a wide range of use cases where neither method alone is sufficient.

The Hybrid AI Approach

The best solution isn't necessarily a choice between on-device processing or cloud-based AI—it's likely a combination of both. A hybrid approach ensures low-latency responsiveness by handling immediate, time-sensitive tasks on-device while leveraging the cloud for computationally intensive processing. This method allows developers to assign tasks based on performance needs, ensuring fast, natural user interactions while maintaining flexibility and scalability. With intelligent load balancing, AI applications can deliver the best possible experience while optimizing for privacy, efficiency, and real time interaction.

Limitations of Current Solutions

Developers attempt to use existing tools to execute this strategy but often fall short. WebRTC, while widely used for traditional VoIP applications, was not built for AI-powered speech processing. It struggles with accurate voice detection, real time noise suppression, and smooth conversational turn-taking. Meanwhile, platform-specific APIs from Apple and Android provide native audio processing tools. Still, they either lack flexibility (as seen on iOS) or are inconsistent across devices (as seen on Android). Relying solely on cloud-based AI is not a viable alternative, as sending all audio processing to the cloud introduces latency, leading to unnatural delays that degrade real time interactions. Without a more adaptable solution, developers grapple with high latency, poor real time detection, and platform-specific limitations that ultimately diminish the user experience.

New Tools Built for AI

The Switchboard SDK circumvents these limitations by allowing developers to construct flexible, high-performance audio pipelines. Unlike platform-restricted APIs, Switchboard provides a comprehensive library of modular first- and third-party audio nodes, enabling developers to create custom audio graphs without requiring deep expertise in audio programming. By abstracting platform-specific details, Switchboard ensures that the same pipeline works consistently across Android and iOS (among other platforms), eliminating the need to build and maintain separate solutions for each platform.

Switchboard also provides hybrid processing flexibility, allowing developers to determine whether tasks should run on-device or in the cloud. This capability is crucial for optimizing performance, privacy, and resource efficiency, allowing developers to fine-tune solutions based on specific use cases and hardware constraints.

How Switchboard Solves These Challenges

Diving in more deeply, Switchboard directly addresses the key challenges that Android and iOS present by optimizing latency, improving real time voice interactions, and ensuring platform consistency. For Android, where fragmentation creates unpredictable audio behavior, Switchboard abstracts away hardware differences by providing a unified, high-performance audio pipeline that works across diverse devices. It eliminates the need for developers to manually optimize for various microphones, audio chips, and software configurations. On iOS, where strict system controls limit access to lower-level audio processing, Switchboard offers a flexible framework that works within Apple's constraints while allowing advanced customization of AI-driven audio features.

Switchboard can significantly reduce delays and enhance conversational flow by enabling real time, on-device audio processing. It allows for natural back-and-forth interactions without noticeable lag, adds more flexibility around noise suppression and echo cancellation and allows audio pipelines to be configured for AI-driven speech applications.

Switchboard also enables developers to fine-tune hybrid AI workflows by seamlessly integrating cloud-based processing while keeping time-sensitive tasks local. This allows AI models to leverage powerful cloud-based machine learning for deep speech analysis while ensuring real time responsiveness—such as interruption detection, latency-sensitive audio transformations, and local speech enhancement—remains fast and efficient. By giving developers precise control over how and where audio processing occurs, Switchboard makes it possible to build AI-powered voice applications that are both high-performing and adaptable to platform constraints.

Beyond basic audio processing, Switchboard enables advanced Voice Activity Detection (VAD) to distinguish between primary speech, background chatter, and incidental noises. Switchboard can support VAD designed for AI-driven interactions, interpreting speech intent more accurately. This ensures that AI agents, for example, can respond naturally without being falsely triggered by background noise or momentary interruptions, improving real time communication and enhancing the the user experience.

Conclusion

Developing AI-powered audio applications across Android and iOS is challenging due to fragmentation, outdated RTC stacks, and platform limitations. A hybrid AI model that balances on-device and cloud-based processing is the best way forward. Switchboard makes this possible by providing a flexible, powerful SDK that gives developers control over their audio pipelines without the constraints of WebRTC or platform-native APIs. For developers looking to build high-performance, real time AI audio applications, Switchboard is the tool that makes it easier, faster, and more reliable.