On the percussion side, I really liked Frontier Design Group's percussion app Cowbell Plus (V. 1.2, $1.99) and DigiDrummer (V. 2.7, Magnus Larsson; $1.99), which gives you eight drum pads and a range of kit sounds.

FEATURES, AT A GLANCE

Claves
Cowbell
Drum Sticks
Egg Shakers
Hand Clap
Maracas
Rim Shot
Rim Tap
Sleigh Bells
Snare Drum
Tambourine
Triangle
Tube Shaker
Vibraslap
Woodblock

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