The number of apps on both app stores of IOS and Android has exceeded millions. 1 million is simply an understatement so you can assume how many app users would exist in the current time. Therefore, the process of app development should be quick and simple. User interface design is one aspect that consumes the most time and the code is written separately for IOS and Android. If you think you want an app made quickly and it should be for both the operating systems then it is better to contact a react native app development agency. Any other fast development approach?