No idea what I'd do with the app, what it does, or why I'd want it. "Customize a tour to a point of interest" is not meaning heavy for me. I've never customized a tour in my life. I don't know why I'd want to. You'll want to A/B/C test lots of headlines/copy, but I'd say this is a pretty rough start.
What are hidden gems? Restaurants? Tourist spots?
Your headline/copy needs to paint a picture to the target user and make someone feel that this is the PERFECT app for them. Who is that? Travelers? Partiers? Geocachers? Bored folks on weekend? I'd start with very narrow positioning and expand from there.
The screenshot is you greatest weapon for communication and the first thing people will look at. It's a busy map with a lot of colorful pins. What are the pins? What do the colors mean? What do the icons mean?