I’m building an app in free version. My app is for multiple users. I want to know that how many devices can use the app at the same time.
With a free account, only you can use your project (for testing). I suppose you could share a link to your project and other people could help you test it but that’s not a permanent way to have multiple people use an app. At least that’s the case for iOS (see below for Android).
With a Pro Plan or higher, you can publish to app stores and an unlimited number of people can use your apps.
You can with a free plan distribute the APK (or IPA not sure) file to your friends.
But if you want to publish it you have to pay