Apple has launched the iPad Pro 2021 and the new Apple TV yesterday, but Apple has not added U1 positioning chip for these two new devices. Because the full function of AirTag needs to work with devices with U1 chip, users can only use AirTag with iPhone.
Currently, the only devices equipped with U1 chip are iPhone 11 and newer iPhone series, Apple Watch Series 6. Note that iPhone SE (second generation) is also not equipped with U1 chip.
At the beginning of the month, Apple announced the launch of the Find My program, allowing third-party accessories to integrate with the Find My application. Equipped with U1 chip can be more ready to find related products.