If you linked Animal Crossing: Pocket Camp to your Nintendo Account on your old device, you can continue to use your Leaf Tickets and other purchased items if you link your new device to your Nintendo Account.
However, please be aware that Leaf Tickets obtained or purchased in the game on operating systems other than Android are not compatible with and cannot be used on Android devices.
Please see the answer to the Is it possible to continue using Animal Crossing: Pocket Camp as the same user if I change devices or obtain a new one? question in this FAQ for more information on the procedure for linking a Nintendo Account.