I have a domain with GoDaddy and a server with digital ocean.
I wonder if I should set up my email address that goes with my domain on the server side or on the domain host?
I saw here that it's not good to setup email on my own server. Should I use a service like mailgun or sparkpost right from the beginning without setting up anything on the server?
It's not good if you plan to send tons of mails...so it depends on your application...frequency, number of users, number of emails, goals...On my shared hosting, I know I'm "limited" to send 500 mails / hour...
You don't need to configurate all at the begining, and it's so easy to switch from a provider to another...that I would not be afraid about that.
But some more experienced people could correct me if I'm wrong.
There are some nice videos from Jeff about mailchimp and mandrill explaining how to configurate