Good idea to offer a demo on homepage. Communicates more effectively than any explanation of the features.

However, before one clicks "try demo", the image of the app is a bit confusing. It's not immediately clear what I'm looking at here. I get it's a screenshot of the app - but maybe a screenshot of a more clear moment in the UI. I see a bunch of confetti, some flags, a big button...a bit confusing.

One thing that could contribute to building more trust is an explanation for the methodology of how it works. Don't rely on just the demo to show this off! You could spend a little bit of space later on the site to mention how your app is based on some kind of academic linguistic research or something along those lines. It says "created by experts" - make me believe it in supporting copy below.

Finally, how does this work? It might seem self-evident to you that for example maybe the app uses AI to listen and critique pronunciation. But it's important to explain how it works. You call out competitor apps for being too complex but that kind of relies on knowing how those work to explain how yours works. Better to just explain yourself!

Good luck.