Yes other users have to get metamask or equivalent to interact with the dapp. However if all you need is to get information from the blockchain, you can implement infura which allows you go the data from there without needing an account in the web app.

So people could see content from the blockchain without having an account. If you want your dapp to interact with web 2.0 services, the fastest solution is to use an external oracle which is just a trusted server that provides information to your smart contract.