Deezer
Organize your playlists by musical intensity
User research
Validating the need on community forums
In November 2025, streaming platforms served millions of daily users, yet none allowed organizing playlists by musical energy. I analyzed community forums across the three major platforms to validate this need.
Community
threads
17
Platforms
concerned *
3
Unanswered
request
2017
Users build playlists around specific moments (a morning run, an intense work session, a wind-down before sleep). But no platform offered energy-based sorting. The only option: manually reorder, track by track.
Behind these numbers, two recurring profiles emerge:
Lucas, 28, runner
He creates long playlists for his runs but spends 10 minutes manually reordering before each session. He wants to build intensity progressively without interrupting his flow.
Camille, 34, remote worker
She uses music to manage her energy throughout the day. She alternates between focus and relaxation but has no way to switch moods without creating a new playlist.
Both profiles share the same need: controlling intensity based on the moment, not delegating to an algorithm.
Note: since this concept was created (November 2025), Spotify launched Smart Reorder (February 2026) and Apple Music introduced AutoMix (iOS 26), two approaches to automatic BPM-based transitions. My proposal stands out by offering explicit user control: sorting by intensity sections (calm → energetic or the reverse), not an opaque algorithmic reordering.
*Deezer Community · Spotify Community · Apple Discussions
Explored concepts
Three directions evaluated on control, feasibility, and timeline
With this need confirmed, the question became: what form should the solution take? I explored three directions, evaluated on three criteria: user control, technical feasibility, validation timeline.
Automatic DJ mode
Auto-sort on creation
Manual sort panel
Each direction was evaluated against the three criteria:
Automatic DJ mode :
Smooth transitions between tracks based on BPM, like a DJ set. Immersive experience but major technical complexity, scope too large to validate the need quickly.
Auto-sort on creation :
Deezer detects varied BPMs and offers to organize on add. Proactive, but only covers new playlists and ignores the need to change sorting based on the moment.
Manual sort panel :
Dedicated icon in the action bar with flexible sorting options. Full user control, applies to all playlists, realistic scope.
The manual sort panel checks all three criteria: the user retains full control over playlist organization, the feature builds on existing native components (immediate feasibility), and the scope allows delivering a testable prototype in a few weeks. If the core need is validated, DJ mode becomes the next iteration, not the starting point.
The goal: integrate into the existing Deezer experience without disrupting the listening flow. A single entry point, an icon in the playlist action bar, that opens a sort panel reusing native app components.
Playlist → BPM icon → Sort options → List reorganized by intensity
Mobile-first: 89% of streaming listening happens on smartphones (1.42B mobile users vs 148M on desktop).
Prototype
From paper wireframes to Deezer interfaces
The direction was set: the manual sort panel. Before moving to high fidelity, I validated the flow on paper wireframes to confirm friction-free integration into the existing experience.
The prototype had two hypotheses to validate: the icon would be discoverable, and section-based sorting would be understood without explanation. Every screen reuses native Deezer components, zero new patterns, maximum familiarity.
The BPM icon fits into the existing action bar, zero disruption to the usual flow.
The user activates sorting and immediately sees their playlist grouped by intensity sections.
Sorting reverses to accompany a return to calm (post-workout, end of day, transition to sleep).
The user chooses their level of detail. Minimal for casual users, complete for technical ones.
User testing
Validating discoverability and sort comprehension
I submitted the prototype to 4 testers with two concrete tasks: organize a playlist for working out, and navigate the sorting options.
4
TestersTasks completed
without blocking
100%
Find the
terminology clear
75%
Would recommend
the feature
100%
Critical friction point: the icon
The heart + cardiogram icon poses a discoverability issue. 50% of testers suggest level bars to better symbolize intensity.
The need is situational (sports 50%, parties 50%), not systematic. The feature must remain accessible without being intrusive.
Next iteration: replace the heart+cardiogram icon with level bars as suggested by testers, and test icon placement (action bar vs context menu) to optimize discoverability without adding visual noise.
This concept shows that a long-standing need can find a simple, quickly testable answer by building on existing user behaviors. Next step: validate the new icon at a larger scale, and explore automatic DJ mode as a natural evolution of manual sorting.
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