B4X is unique as product. There can be (and there are) many competitors. But B4X remains a unique product of its kind. In particular, in the last 3 years it has reached a level that is truly unique on the market. I'm sure, looking at the latest futures that Erel has included in B4X that we will soon have a single product that will allow us to create cross reference applications even more easily and quickly.
Let's not forget that B4X also has products that allow development for ANDROID, IOS, WINDOWS, MAC, LINUX, ARDUINO, RASPBERRY PI, ESP8266, AND MORE.
Ultimately i don't think there are tools like B4X either for ease of use or for development speed