Just installed B4A as it's shown on the official website and i still can't build & run an example project (Hello world).
I installed the app on my cellphone too and successfully connected to it, installed B4A Designer as the firt app asked to.
I'm getting this error, sorry it's in French. But basically it says that it doesn't find a file (i m wondering which one...).
Install exactly has shown here:B4A installation
Especially at Step 2 this: Download the required resources. Click on that link. That step I forgot too. And then you get errors. If you follow exactly without haste. It will work OK.