GMApp

GMApp is a background playback-enabled soundboard, audio sampler, and timer for Murder Mystery, story-playing games, TRPG game masters, and theater productions. Control BGM, ambience, and sound effects from your smartphone or tablet to create immersive live and online experiences.

Designed for:
• Murder Mystery and TRPG game masters, keepers, and facilitators
• Sound operators for stage plays, reading performances, comedy shows, and small productions
• Online sessions on Discord and other voice chat tools
• Creators who manage large sound libraries by scenario, scene, or phase

Use cases:
■ Murder Mystery / Story-Playing Games
Seamlessly crossfade BGM as the game moves between investigation, discussion, secret talk, and climax scenes. Trigger dramatic sound effects with a single tap during shocking reveals. Page management lets you instantly switch sound sets for each scenario.

■ TRPG
Layer ambience and BGM for dungeon exploration, taverns, battles, and more. With polyphonic playback and up to 32 simultaneous sounds, GMApp helps pull players deep into the world of your story.

■ Theater and Stage Performances
Bring flexible sound operation to small productions, amateur theater groups, rehearsals, and live shows using just one smartphone or tablet. Handle scene-change BGM, sound effects, curtain calls, and timed cues with confidence.

Key features:
◆ 16-Pad Soundboard with Up to 100 Pages
Each page provides an intuitive 4×4 layout with 16 pads. You can create up to 100 pages, for a total of 1,600 pads, and organize BGM and sound effects by scenario phase. Page locking helps prevent accidental edits during performance.

◆ Three Playback Modes
Set the best playback behavior for each pad:
• Polyphony: Layer ambience, BGM, and sound effects.
• Monophonic: Switch cleanly between single audio sources.
• Crossfade: Smoothly transition between BGM tracks with adjustable fade duration.
Tap actions can be set to retrigger from the beginning or toggle pause/resume.

◆ Fully Customizable Pads
Customize each pad with a display name, button color, loop setting, and volume gain from 0.1x to 1.0x. Clear names and colors help reduce mistakes during tense sessions.

◆ Direct Import and Cloud Support
Import audio through the standard Share menu, Google Drive, Dropbox, or ZIP files. Batch ZIP import makes it easy to prepare large sound sets quickly.

◆ Bluetooth Sleep Prevention
Help prevent Bluetooth speakers from sleeping during long quiet scenes, reducing the risk of the beginning of a sound being cut off.

◆ Full-Screen Timer
Use stopwatch and countdown modes from 1 second to 24 hours. Full-screen display makes it easy to show remaining time to players during in-person sessions.

◆ Sharing and Backup
Export and import pad settings and audio files as ZIP files by page. Share sound sets with other GMs or assistant operators, and keep backups for future performances. When sharing audio materials, please respect each provider’s terms of use and copyright.

Technical specifications:
• Pad layout: 16 pads per page / up to 100 pages / total 1,600 pads
• Simultaneous playback: Up to 32 sounds in polyphonic mode
• Supported audio formats: AAC / AIF / AIFF / CAF / FLAC / M4A / MP3 / OGG / WAV
Some compatibility may vary depending on device and OS.
• Timer: Stopwatch / Countdown from 1 second to 24 hours
• Languages: Japanese / English / Simplified Chinese / Traditional Chinese

Commercial use and streaming use are allowed.

Bring sound to your story.