If you still have the game running on the Android phone, I suggest you screenshot your player ID and keep it in a safe place before any further actions. Now this is out of the way, we can go on and try the following.
Years ago PopCap has provided a method which supports transfering game save progress cross platform. In your case, the steps are below.
1. On your Android phone, start up PVZ2 App,
2. click the cloud button, register your email address so it ties to your account. (there is a 20 gems reward if it is your first time register)
3. On your new iPhone, perform the same email register, you will be given a code to your email address. Use this code to verify and confirm you are the account holder.
4. Once verification complete, you will receive an ID conflict message and given a choice to recover your old account from the Android phone. Please make sure you select the right one with your progress, if you do decide to chose to start with a fresh one, your progress will be overwritten.
