Gusto Co

So far this app works great for us. I am happy to see that the developers finally decided to offer it for free. They also have "cafeteria" style option where you can build from the free plan and choose ways for your customers to earn points that suit your business. That's a big plus for us! Being able to embed the app into a page and edit css is also a plus.

Works great. We are slowly growing our email list!