I was looking for a way to create an app easily and efficiently, then I found AppSheet. App Sheet is a platform that you can create your app from you DATA as a database, AKA data-driven. That is when you want to know what data do you want to collect to keep how to manipulate them then you can create you app. AppSheet let you do just that!
AppSheet was taken over by Google and it is a common platform and support all kind of users. There are a free version, and paid versions.
I created lots of my apps online. Some of them, I still use until now! Take a look and explore AppSheet it is a great platform!