We were retained by drumming expert Bob Everett to create an iOS app for teaching drumming. If his name sounds familiar, it may be because his son, Shawn Everett, is a six time Grammy award winner as the recording engineer for groups such as The Killers, Alabama Shakes, and The War on Drugs.
Bob's idea was to replace traditional drum notation with something more intuitive: a bit like a video game. Vertical lines represent items in a drum kit. Symbols on those lines represent ways of striking the drum kit item (for example, a rim shot, or a symbol crash).
The drum score drops down the screen at the song's tempo, and you make each sound at the moment when its symbol hits the "play line". The user can pick which lesson to work on, and what tempo to play at. Icons representing the player's hands and feet flash when they are to be used.
Each bar of music is a different colour, and the number of beats per bar varies with the time signature of the music.
Dr. Heerema, who has many years of experience in iOS app development, used the declarative Swift UI language to build the user interface, and Swift for the application itself. The drum sounds, recorded at the Banff Centre for the Performing Arts, are played with sub-millisecond timing precision. The Combine reactive framework is used to send event messages to various components of the user interface, such as the hand and foot icons.
A video of the App in action is shown below: