This is due to carrier support for certain LTE radio frequencies. For more information about international roaming rates and policies, contact your wireless carrier.
To see if your status is up to date, if you are not already a member of the program, you can check your upgrade status. You can upgrade online or in person at an Apple Store to speak with a specialist. After six months, you can upgrade as long as you have made at least 12 payments. You can upgrade if you need to pay an extra amount to cover your 12 payments. As part of the program we will help you trade in your iPhone. Please do not use the standard Apple Trade In option to trade in your iPhone.
It is notable that the Apple A15 Bionic Chip is included in the Pro and Max models. This is Apple's most powerful mobile processor, which Apple claims is up to 50% faster than other competitors. The Pro Max as well as the Pro Max have an upgraded 5-core GPU. These are joined by a 120Hz screen, an upgraded battery, and improved camera sensor to make this a very powerful mobile device indeed.