When we develop and run a non-decentralized application it causes costs for using cloud server.
How much does it cost to develop and run dApp on Ethereum or Hyperledger fabric? Which one is cheaper?
Keeping the app in the blockchain doesn't cost anything. The following is true at least for Ethereum (no idea about Hyperledger):
You pay for development
You pay for deployment (gas costs)
You pay for using the app (gas costs) - except for read-only operations. Depending on the implementation typically anyone can interact with the app on the blockchain so everyone pays their own transaction costs.
No other costs such as "upkeep" (except of course further development & updates & etc)
It's impossible to give any numbers as each phase has wildly varying costs.
The most essential distinction between Hyperledger and Ethereum is the intent they are designed for.
Ethereum runs the Smart Contracts on the EVM for applications that are attributed to being decentralized and are for mass consumption.
On the other hand, Hyperledger leverages blockchain technology for business. It is designed to support pluggable implementations of components delivering high degrees of confidentiality, resilience and scalability. Hyperledger has a modular architecture and provides a lot of flexibility in how you want to use it. Its extensible architecture provides futuristic solutions for enterprise blockchains.
It will cost gas to deploy your contract to the blockchain, but once it's up, there is no cost to keep it up. Any function calls will require a transaction. In Ethereum, every transaction on the blockchain costs a small amount of gas. Gas is payed by whoever submits the transaction (this will usually be one of your users rather than your organization). Each transaction can cost anywhere from a small fraction of a cent to several dollars. You can pay more to speed up your transaction. Your costs will depend on the deployment size of your contract, the number of transactions that need to be made, the logical complexity of your transactions, and how fast you want your transactions to be.
Hyperledger is a bit of a different beast. I'm not very familiar with it, but I know it is highly modular and customization. Your costs will depend on what modules you implement.