Generally, users of decentralized applications have to perform technical operations to interact with blockchains through custom tools to be installed. users have to confirm their actions for all interactions with the blockchain.
For Ethereum: Metamask chrome plugin has a setup requiring 10 to 20 steps, and depends on Google services availability for setup.
The Ethereum official wallet: mist, requires a few hundred gigabytes and several hours of setup.
Opera announced in July 2018 as an integration of crypto wallets into mobile browsers, has no release date yet.
Scatter is another chrome browser plugin to store an EOS or Ethereum private key. With advanced setup, users can avoid confirming all step by blockchain interactions on EOS blockchains.
Users have to use crypto wallets which are disrupting application usage: the future of Ethereum doesn't have wallets.
Users also have to buy tokens, a complex process of hours to weeks due to KYC constraints on exchanges. They have to do it for 2 distinct tokens, the blockchain token, and the dApp crypto token: this is the economic abstraction issue, which solution is still being designed by the Ethereum community.