We at swetrix.com have made a decision to drop support for the free tier and introduce a $5 per month tier instead.
We did it because there are a lot of people who simply stick to the free tier and never upgrade, so we decided to mostly focus on paid user: starting from now all new customers can sign up for a 14 days no credit card needed free trial and upgrade to a paid tier or stop using the service. All the people who registered for a free tier before we dropped it can still use it for free, forever.
As for now, this experiment is doing well: before we've had about 2-3 signups a day, the trend is almost the same. We're receiving 1-3 sign-ups per day, but now the customers use trial subscription and before signing up they clearly understand that our service is a paid service.
We'll see how this experiment goes, I'll keep all of you updated, but as for now, I feel pretty confident about it.