Is the premium plan a bunch of new features that weren't available in the beta? If so, I'd say just release them and send out an email.

If the premium plan is going to lock features that current users already have, I would put a delay on it going into effect for them... Send out an email saying they will be able to keep using the premium features for like a month or whatever, then they will lose them. Throw in a coupon code or another offer to help convince them to upgrade.

Yup, I'd recommend doing what @pugson said. I have my main email address as [email protected], then I set up an alias for every domain I have... Then I can send and receive emails from [email protected] without buying another email plan.

I just launched ceev.io a few weeks ago and was wondering the same thing. I had everything available for free at first, but wanted to monetize it a bit.

I worked on a few new features - 2 new resume templates and two new editing options - and added those under a paywall. It wasn't much, but I also promised people who upgraded new exclusive features weekly. At least for Ceev.io, that worked pretty well. I got many more sales than I was expecting, and it seems people who bought it right away were not disappointed even though there weren't many paid features.

So maybe start small - add a few features for paid users, then just keep adding features and raising the price. Let users know that by paying, they will continue to get exclusive features, and they are also supporting the project/website/community. For many people, that will be enough to start, and as you add more paid features, more people should think it's worth the price and will be more willing to pay.

I think it'd be cool to track version releases and somehow tie it into to-dos. So when I put an update out, I can keep track of it and have all of the todos I completed for that release under it.