My country has been badly affected by climate change due to heavy deforestation. So many campaigns arose planting more trees. However, to reduce my effort in gardening, I made something that water my plants based on an Android app.
The concept is simple: I designed a web server using ESP8266. Changed index a bit. Also, the ESP8266 controls the relay to water pump.
The second component is an Arduino Nano, which takes readings from DHT11 and displays on an OLED.
Please check this video out!