Example of ERC721 token based on the real smartphones and bridge between two different blockchains.
This solution was made to solve the problem of exchanging information about tokens in different blockchains. It is very expensive to do simple actions on the token in the main network. To fix this, somebody goes to cheaper blockchains, but it's not very profitable to sell a token there. So, with this solution token regularly is in the home(cheap) network where user can do various actions with it, but for sale the token should be transferred to a more expensive network, where it is profitable for user to sell it. The example is based on smartphones, the smartphones have the owner, the color, the weight, the model and the brand name. User can look at all this information in a home (cheap) network. But if he wants to sell them, he will sell them in a more profitable network.