We don’t like Ads too but they help us to sustain the project and keep the app free.
There are few ways to remove to Ads:
Become a contributor, add as many WiFi as you can, update existing WiFi and share the app with your friends. All of that will generate points for you. Ads will be gone forever once you’ve reached 2000 points. Which can be accomplished in few days.
Second option is to remove them via In-App purchase by going to the Settings section of WiFi Map.