Did anyone a Bluetooth extension?

I’m currently working on (among other things) an analog board game based on an old computer game of mine. It does include digital elements, though — an app that communicates over Bluetooth with an ESP32 mounted on the board.

For the app I wanted to use Defold, since it lets me put something together fairly quickly. That meant I had to develop a Bluetooth extension, and I went with SimpleBLE for that, which turned out to be pretty tricky to compile and get it run. It works now and I can talk to the ESP32 from Defold over Bluetooth, but I wanted to ask whether anyone here has already built a similar Bluetooth extension, and if so, which lib/SDK it was based on. SimpleBLE unfortunately isn’t exactly cheap.