Oumefar 8 Channel Bluetooth 4.0 Relay Android Mobile Remote Control Switch DC 12V 10A Relay Module for Android Phones with Bluetooth 4.0

This 8 Channel Bluetooth 4.0 Relay Android Mobile Remote Control Switch DC 12V 10A Relay Module comes without instructions or a power supply, and the relays require 12V DC to power. However, pairing the device with an Android phone is relatively easy using the password "1234" (not "123456"). Writing an Android app is not too difficult, but some coding knowledge is required. The relays are latching and will stay in their toggled position. Commands to send to the controller are available in the listing, with the peripheral name being "BT04-A," service UUID being "FFE0," and the characteristic for writing being "FFE2." However, commands must be sent as hexadecimal, not a string. While it works well, users have requested the addition of codes for momentary switches and the ability to group the relay switches. The product doesn't come with any packaging other than a bubble wrap bag with static foil, and the company doesn't come with instructions, leaving customers to figure out the setup themselves. Some users have found it challenging to get info from the seller or to get the product to connect to an app, making it not worthwhile.