The latest version of ChordEase (1.0.09) can be synchronized with an external device. Timing synchronization is implemented via MIDI clock messages, combined with the Start, Stop, Continue, and Song Position MIDI messages. ChordEase can be a slave or a master. For details, see Patch Bar/Sync in the documentation.
This version also adds a "Thirds" non-diatonic notes rule, which causes successive white keys to form the cycle of thirds. This makes it much easier (and more fun) to play arpeggios. Interval distances are greatly reduced: each input octave spans two output octaves. This facilitates the playing of melodic lines that are unusually wide in terms of range. It also could be of interest to people with physical limitations that might otherwise prevent them from playing wide intervals.