How do I get users to on my mobile app before I launch?

Just to understand, what is the value to the user for creating an itinerary?

The users creating these itineraries, who are essential the content creators, receive star ratings and comments based on how well that particular itinerary was for a user who decided to try the itinerary. (I.e John creates a 1st date itinerary. Mike, who is looking to plan a 1st date selects John's 1st itinerary. After going on that date, Mike really enjoyed it and then goes back to give John a 4 star rating and comment on how great his itinerary was). For future iterations badges an points may be an option.

To add, receiving high ratings from enough members enables him to be featured as Member of the week for example, enticing these creators to compete

The users creating these itineraries, who are essential the content creators, receive star ratings and comments based on how well that particular itinerary was for a user who decided to try the itinerary. (I.e John creates a 1st date itinerary. Mike, who is looking to plan a 1st date selects John's 1st itinerary. After going on that date, Mike really enjoyed it and then goes back to give John a 4 star rating and comment on how great his itinerary was). For future iterations badges an points may be an option.

To add, receiving high ratings from enough members enables him to be featured as Member of the week for example, enticing these creators to compete