To connect a mouse or trackpad to an iPhone or iPad in iOS 18 and iPadOS 18, follow these steps:
° Open the Settings app and tap Bluetooth.
° Turn on Bluetooth.
° Put your mouse or trackpad into pairing mode.
° Select your mouse or trackpad from the list to pair it. ==
° Follow the onscreen instructions
You can also use a Bluetooth mouse with an iPhone using AssistiveTouch:
° Go to Settings > Accessibility.
° Select Touch.
° Select AssistiveTouch > Devices.
° Select Bluetooth Devices.
° Select your device from the list.
You can customize the pointer’s appearance and behavior by going to Settings > Accessibility > Pointer Control.
(This how-to is based on my experiences and info on Apple’s support pages.)