Just another doorbell project. Me too wanted to keep use of the current doorbell we have. But when I was outside the house I sometimes missed the front doorbell ringing. I have no desire for a wifi doorbell (yet), so was looking for a simple and cheap solution. Because I mainly use Xiaomi Aqara stuff (about 25 devices) I came up with the idea to use a door/window sensor to give me a signal on my mobile phone. I removed the small glass tube from the sensor and connected a wire to both soldering point. These are connected to the doorbell button wires. See photo. I made a rule to signal me on every change of the contact. It works great for me!
