Important update:
I have seen a lot of complains here about the onesignal plugin not working, and that’s unfortunate.
My app is almost done and I really need push notifications.
I did the only thing that I could: I’ve made the plugin myself (well I paid a freelancer, a very talented freelancer actually). And for me, on iOS it works like a charm! It also has badges, so on iOS you can increase the number, decrease it, remove it, whatever you desire.
You can also send mass messages, segmented messages, individual ones, whatever your heart desires 
I will officially launch it in less than 24 hours. Still need to complete the tutorial/documentation and to test it on Android (should work just fine, but still).
Is there anyone that want to help me test it in private before that?
Just give me your bubble app name (subdomain basically) and I will add you in 8-10 hours.
Thank you!
The plugin will be free forever