5-6-7-8

available under: vera-bernhard.github.io/5-6-7-8

5-6-7-8 is a Flutter app for music-based training and routines, such as team aerobics, dance, gymnastics, rhythmic gymnastics, cheerleading, figure skating, artistic swimming, and show groups. It lets you build a small song library, add named timestamps to songs, and replay single timestamps or whole timestamp ranges with an optional lead-in.

Current Functionality

• Import audio files with these extensions: mp3, wav, m4a, aac, ogg
• Name each imported song before adding it to the library
• Persist songs and timestamps locally on device or in browser storage for the PWA
• Browse a library of saved songs
• Rename or delete songs from the library
• Open a song in the player view
• Play, pause, and seek through the track
• Use a generated waveform-style seek area for scrubbing
• Add timestamps with a name and editable time value
• Store unnamed timestamps as well
• Replay a timestamp with a configurable lead-in of 0s, 1s, 3s, or 5s
• Long-press timestamps to mark a contiguous segment
• Replay the selected segment, again with the configured lead-in
• Mark timestamps as shuffle-enabled
• Play a random shuffle-enabled segment with the Random button
• Delete individual timestamps

Storage

Songs and timestamps are stored locally using Hive.

• The PWA stores data in browser storage (IndexedDB)
• For an installable PWA, deploy over HTTPS so the app can be installed and use persistent browser storage

PWA: What and Why

A PWA (Progressive Web App) is a website that can be installed like an app and launched from the home screen/app launcher.

Why this makes sense for 5-6-7-8:

• No app store release is required for each update
• Works on Android, iOS, and desktop browsers from one deployment
• Fast access during training sessions (open from home screen like an app)
• Offline use is possible for already loaded app files and locally stored songs and timestamps
• Local-first storage is practical for routine/music practice without cloud setup

Offline Functionality

The app is designed to work offline after songs are already in local storage.

• Playback and timestamp workflows work without network access once audio is imported
• Song/timestamp changes are stored locally and remain available offline
• The app has no cloud sync; data stays on the current device/browser profile
• For PWA use, first load/install over HTTPS while online, then offline use is available for locally stored content

Run

Requires a Flutter SDK installation.

flutter pub get
flutter run -d chrome

Build

Build for PWA/web:

flutter build web --release

Notes

• The waveform display is a generated visual seek aid, not an analyzed audio waveform
• The app currently keeps audio bytes with each stored song, which makes the web/PWA build self-contained but can increase browser storage usage for large libraries

Tech Stack

• Flutter
• Audio playback: just_audio
• Local storage: hive_flutter
• File picking: file_picker