Might not the thing you are looking for, but I tried to find a replacement for Keep a year ago and somehow stuck with a todo.txt file. It can be edited in a normal text editor but I use Markor and todo.txt on Android and Sleek on desktop. Sync is fine via your preferred sync tool.

Mhh might be a Connect problem, never tried it. I’m using Jebora, Liftoff or wefwef at the moment.

Check if you enabled the notifications in the profile settings. They are working for me pretty reliably.