I'm Stefan, a freelance developer who developed Propi, an app that analyzes text from freelance proposals and offers suggestions for improvement.
The app also has a proofreading option that points out any grammatical error.
The idea came up after talking with tens of freelancers and the same question popped: "How do I write proposals that make clients hire me?"
I couldn't find any app that does that, so I made Propi:
https://play.google.com/store/apps/details?id=com.stefanionescu.propi
What do you think about it?