What it’s like managing 10 million users as a solo developer

A major takeaway from this project is the importance of updating in phases instead of trying to update for all users at the same time. I had once pushed the wrong update to all of my users — it did not go well and a lot of users crashed.
It’s also important to respond to reviews to help get a better rating as a service. Try to respond to as many review as you can. Some users will even email you back and give really valuable feedback. 
Localize to make all users understand your app. I have translated the app into Spanish and Portuguese, since most of users live in Brazil, Mexico and Argentina, and they do not all speak English. Even the Play Store screenshots are localized to get more downloads.
Just because you understand your app doesn’t mean someone else will. Since a large percentage of my users are not very tech-savvy, I have to test new features with my parents first and asses their reaction to ensure that everything is easy to understand. 
It’s also important to get a social media presence from the start, I just recently started using Instagram and Facebook, and have gathered 60,000 followers in a short period of time. Social media leads to new users who you can easily reach.

Sven van der Zee, Founder PlayStudio apps