Wales striker Church joins on a two-year deal after being released by Charlton, while USA international keeper Cropper was let go by Southampton and has signed a one-year contract along with winger Jennings, who left Barnsley at the end of last season.
“I’m excited to have them on board,” Robinson told mkdons.com. “They will all bring different attributes to the group.
“Cody has got tremendous potential and he fits the type of the person we want around the place. He’s a good size, got a great work ethic and wants to learn.
“This is an opportunity for Dale, who knows he’s got work to do, but we all saw last time what he can do – he lifted the team and contributed to some good results.
“Churchy is a really top lad, a good player and can score goals. He will add tremendous quality to our team.”
Church said: “I’m excited to be here. With everything in place here, it was the perfect move for me and the ambition of the club is massive and I wanted to be a part of that.”
Cropper said: “It’s a great opportunity for myself and I’m very pleased to be here. I want to push on and develop as a goalkeeper.”
And Jennings, who had a loan spell with the Dons last season, added: “I’m really happy to be back. I enjoyed my time a couple of years ago and it was a no-brainer to return – I can’t wait to get going again.”