Decentralized Applications or DApps are basically digital applications or programs that operate on a blockchain or a P2P network of computers. Putting it in another way, the open source software that leverage on blockchain technology is known as Decentralized Application (DApps).
Now that you know what is DApp, let’s move further into the criteria wherein you can judge a DApp:
Open Source: Basically, DApps are govern by autonomy and the consensus or majority of users decide all the changes. Also, the source code of the app is available to all.
Decentralized: To avoid the perils of centralization, all records of the app’s operation needs to be store on a public and decentralized blockchain.
Incentives: The blockchain validators need to incentivized by gratifying them with cryptographic tokens.
Algorithm: The decentralized application community should agree to a cryptographic algorithm, basically to show the proof of value.