The Altis AI Personal Trainer.
NB : We first looked at this one in the weekly Strength & Fitness Newsletter (part of the Strength Kit). If you'd like to have it sent to you automatically (free!) each week, just add your email here.
We also discuss a number of training-related books. If you're looking for the full list of the ones I'm checking out personally, swing by Goodreads. You can also suggest new ones there (or via this site's contact page) - I'm always on the lookout for more literary goodness.