The journey from zero to $10K MRR took about 1 year. The journey from $10K MRR to $20K MRR took about 6 months.
The more customers I get, the more development is led by them. I still add items to the backlog based on my own ideas, but generally they stay there until a customer mentions them — then I prioritise.
The more tutorials I have, the more users convert as they understand the product better. The better my API docs, the more my product appeals to developers, and also reduces my support load.
You might be thinking what contributed to the big spike on X date? The answer is... nothing. Day to day SaaS life is erratic, one day great, next day quiet. But zoom out and you see consistent growth.
During this period I cultivated a more long term view. I stopped obsessively checking my MRR, stopped freaking out over a churned customer, and focused more on the needs of long-term customers.
Sometimes it's good to indulge your inner geek and just build features you think are cool. Face detect has a wow factor that plays well on the marketing site. It's also used extensively by several customers now.
A core strategy going forwards is targeting bigger customers. My experience with retention / churn is typical for SaaS — low tier customers churn fastest, mid and high tier customers stay longest.