I've been using Morse Trainer for Ham Radio on Android to speed up and re-learn morse up to decent QSO speed. I really like this app, it has most of what I need.
One of the modes is own text mode where you can add plain text (which will be sent as CW as is) or comma-separated list mode. In comma-separated-list mode, the words are randomly played back. I've been using this with a set of words commonly used in QSOs.
Here's the list I'm using: