
In a world where emotionally resonant user experiences are an integral part of any company's strategy, music and video have become irreplaceable tools that can offer users moments of joy, relaxation, and connection. Behind these seemingly effortless experiences of flawless playback or personalized playlists lies an intricate web of thoughtful design and complex engineering.
Andrei Trefilov, an iOS engineer at BandLab — a Singapore-based music creation platform with over 100 million users — has spent years navigating these challenges. His expertise in designing and engineering seamless digital experiences sheds light on how these apps captivate users and stand out in a crowded market. In this conversation, he reveals the intricacies behind emotionally connected interfaces, the technical challenges developers face, and the evolving future of media technologies.
The Foundation of Emotionally Connected Interfaces
According to Trefilov, the foundation of emotionally connected interfaces begins with product quality. "No amount of clever features or personalization can compensate for a product riddled with bugs or an interface that feels clunky," he explains. "Users need to trust the app, and that trust stems from stability and usability."
A key trend over the past decade has been the emphasis on personalization. "From tailored content like articles and videos to ads that feel like a natural part of the user journey, personalization has become a core strategy," says Trefilov. He highlights that even advertisements can enhance the experience when aligned with the app's core purpose. "In the best cases, ads feel like a natural extension of the content, appearing smoothly without disrupting the primary experience."
Another increasingly popular approach is imitating live interaction, or, in other words, making interactions feel more human. "Many apps now incorporate conversational language in onboarding flows or error messages, mimicking live interactions and creating a sense of connection," Trefilov adds.
Key Technical Components of Music and Video Apps
For music and video applications, stability and performance are paramount. "With the rise of short-form videos, even a momentary delay can cause users to disengage," Trefilov explains. Achieving smooth playback involves multiple technical components, starting with efficient data delivery.
"Video and audio files are significantly heavier than text-based data, so quick and reliable access is critical," he notes. From a technical perspective, developers handle it through content delivery networks (CDNs), which distribute data across servers to reduce latency, and transcoding, a process which converts raw media into optimized formats and resolutions for various devices, enabling faster loading times and seamless playback.
Another key factor is chunk-based streaming, which ensures that for users, playback begins almost instantly without noticeable delays. "By delivering video in small chunks (typically 3–4 seconds long), rather than downloading the entire file upfront, we can minimize delays and dynamically adjust even under varying network conditions," Trefilov explains.
Platform-native tools provided by platforms like iOS and Android further enhance stability. "These tools are designed by experts and regularly updated to support advanced features like Picture-in-Picture or Apple Vision Pro playback," he notes. While some developers experiment with custom-built players, Trefilov cautions against it. "Creating and maintaining a custom solution requires significant resources and often can't match the reliability of native tools," Trefilov adds.
A major technical hurdle involves handling asynchronous processes. "Simultaneous tasks like playback and loading require precise coordination," Trefilov says. For instance, scrubbing a video timeline might involve fetching data that hasn't been downloaded yet — all while maintaining smooth playback. Mastering these components ensures apps deliver the stability and responsiveness users demand.
Managing Frustrations: Preventing and Resolving Playback Issues
Few things frustrate users more than playback interruptions or crashes. "Even when the problem stems from the user's device or network quality, they often attribute it to the app," Trefilov explains. Proactive measures like robust logging and monitoring systems are key to preventing such issues. "Understanding what devices and network conditions users are working with is critical, and this requires planning from the earliest stages of development," he notes.
Reliability also hinges on rigorous testing. "Automatic and manual testing before each release helps catch problems early," Trefilov shares. However, not all issues are within the app's control — factors like CDN accessibility or regional network constraints can cause interruptions.
Comprehensive logging enables developers to identify and address these external issues quickly.
Scalability is another critical factor. "During peak times, like weekends or holidays, systems must handle surges without crashes or slowdowns," Trefilov notes. "Load testing ensures the platform can manage increased traffic while maintaining a low error-to-user ratio," he says.
Balancing Innovation with Performance in Video Features
Introducing new features can elevate user experiences but requires careful consideration of performance. Andrei Trefilov recalls a notable project where his team introduced a TikTok-style feed within an app initially designed for other purposes. "The challenge was architectural," he explains. "We needed to create a system where full-screen videos, audio tracks, and boosted content could coexist seamlessly within a single queue."
While this feature wasn't core to the app's original purpose, it demonstrated how innovations could enhance functionality without disrupting the primary user experience. "Ensuring seamless playback across audio and video required precise coordination," Trefilov shares.
Performance remained a priority throughout the process. "Users won't appreciate flashy new features if they come at the expense of stability," he emphasizes.
Behind the Seamless Experience
The development of music and video apps goes far beyond technical functionality — it's about crafting emotionally connected experiences that users can rely on and enjoy. Andrei Trefilov's insights pull back the curtain on the "addictive" apps with music and video features that we scroll through and connect emotionally. From a developer's perspective, what seems like a simple and seamless process for users often hides an enormous amount of technical effort and precision.
His work highlights the intricate balance between innovation, stability, and scalability. "If an app feels seamless to use, it's because of the meticulous effort behind the scenes," Trefilov concludes. His insights reveal the hidden complexities of creating the music and video apps we love, merging thoughtful design with cutting-edge engineering to deliver unforgettable user experiences.