Is it difficult to customize an Android app for Wear watches?

Question

Java

There is (will be:) an application for the phone with a map and geolocation.
1. Will it be difficult to transfer all the functionality to the watch? (let's say we already coded it for the phone). Of course, you need a separate GUI, but what about the logic?
2. What to take care of before starting development for all types of devices? Before this experience with the clock was not.
3. Is it true that android watches have exactly the same capabilities as an adult android? Can they be independent of the phone, like a separate device?

Answer 1

For hours, you need to write a companion application. There are some apis for the interaction of the watch with the phone.
Your questions are too general. Do you even look at what Google writes on this topic ?