What are some alternatives?
When comparing BlokDust and Splice Beat Maker, you can also consider the following products
Sampulator - Make (and record) beats on your keyboard
SunVox - SunVox is a small, fast and powerful modular synthesizer with pattern based sequencer (tracker).
Ramsophone - A generative art/music machine. (Be sure to refresh!)
Mubert - Electronic music generated in real-time just for you
Super Looper - Make music in your browser
Rhythm Necklace - Make music with shapes on your phone