Now that you know how to connect to the Ethereum network with its smart contracts and find out which functions a smart contract provides, you can finally implement our first small app!
This lesson is more hands-on, which means you have to build your app on your own!
Since you didn't learn about wallets, you can't change anything on the blockchain, but you can read what's already been written on it by other people around the world. But you get some pointers, so you know how to start. Also, I've already written the app so that you can check out a working example.
The app is an NFT owner finder. A frontend (a simple HTML page is enough) for the ERC271 specification. You already used this spec in the previous lesson.
The idea is a user can enter a contract address and token ID, and the app will ask the Ethereum network for the address of the token owner.
Bonus points for additional information you display in that app:
This lesson concludes the first part of this course. You learned most of the things you can do without your wallet.
You learned about the basic architecture of the Ethereum network how to connect to it via public RPCs and Ethers.js and how to do fundamental interactions with smart contracts on the chain.
You also got introduced to the Ethereum Name Service, which makes interactions with addresses easier.
In this final lesson, you even build your first app!
The next part of this course will introduce you to wallets and transactions, so you can finally make a change! You will do all this with test networks, so you don't have to pay the enormous gas fees currently hampering the Ethereum network.