Yeah it’s a great app, free if you participate in giving load info to other people. Basically when you input your profile as spirit if someone needs a load on a flight you’ll get a notification. Click on it and fill in the loads (either from spirit.com or id90travel.com) and you get a credit. Each time you request a load you use a credit. You start with 5 credits and go from there. It’s very easy to use, and if you don’t want to provide load info you can just buy the credits, which are pretty cheap. There are a ton of users and requests are usually answered shortly. International carriers might not be as quick to reply because the app is spreading via word of mouth.