Get started to Meteor? I never create web app so quickly! For the customization, it depends what are your needs. Meteor is clearly cool to make collaborative web app;
If it's about Mailgun, you can get started for free without any configuration and if you want to send more than 300 emails/day later, you can create a mailgun account and easily integrate your own SMTP credentials into the app using the steps outlined in the blog.
If it's about Mailgun, you can get started for free without any configuration and if you want to send more than 300 emails/day later, you can create a mailgun account and easily integrate your own SMTP credentials into the app using the steps outlined in the blog.