What kind of shields do I need to build this in Arduino?

Hello lainons. Recently I've been having problems with trepassers in my house. I was going to buy an alarm, but most of them are not what I want, and are also very expensive. With this in mind, I decided to build one. ...Ok, I mostly decided to build one because it is fun, to be honest. So, this problem is not that urgent. What I want is something like this: 1- A sensor stays behind my door 2- When someone comes in, the sensor gets the distance 3- If the distance is shorter than some value, a notification pops up on my phone 4- (OPTIONAL) when step 3 happens, a camera turns on, and show me in real time what is in my house. What I've come across that I might need is: 1- Arduino UNO 2- HC-SR04 (ultrasonic sensor) 3- Pixy2 (Camera) 4- ESP8266 Module (to send ultrasonic sensor data or/and camera data to a server) I already have the ultrasonic sensor, and managed to make it calculate a distance and print something when something goes in front of it and shortens the distance. The big problem now is finding out how to send it to a server and make it post and display data on my phone, and which shields to use. Could you lainons help me with arduino shields suggestions that would make it easier, or suggest some approach on how to send and retriveve data from the arduino to my phone? Only knowing if these shields suits my needs would be enough, but since it is a cool project, I am open to suggestions.

Won't the distance be the same since the door never moves? Also not sure what you need the arduino and the esp8266 for. I would just stick with the esp honestly. I think it should be able to do everything & has WiFi built-in so it can be it's own webserver, it just transmit the data easily

>>18490 The esp you mean is just the arduino with integrated wifi? Also, the door not moving is an important point. Since it is behind the door, the alarm should only send a notification when the door is opened (because there is no other way to get in my house besides the front door)

>>18492 >>18470 An ESP8266 used to be sold as a wifi module for arduino but it is actually a pretty good microcontroller itself. People figured out how to use this nicro and build an arduino ide plugin to use it as a standalone arduino with wifi. I think the easyest option here would be to buy a wemos d1 mini which is basically an ESP8266 with pin headers and usb port, basically turning it into an arduino, there are some nice libraries and examples that allow you to set up things like websites and tcp clients on it to make stuff easyer and it has plenty of speed to use your distance sensor. As for using a camera, I'd advice replacing the arduino with a raspberry pi and using a pi camera.