Social media counter

I'd like to make a social media counter for our engineering team to take to events.
I was looking at some projects and it seems quite straight forward, except for a problem our application brings: we're always on a different wifi network. How can I connect it to different networks or do I use an app on our phones to connect it?

thanks!

The ESP8266 has the option to look for strongest network and try to connect to it. If it needs a password to connect you can look at the WiFiManager library, which allows you to configure your device on the fly.