# FAQ

<details>

<summary><strong>What is Zyfi?</strong></summary>

Zyfi is based on a proprietary paymaster that enables gasless transactions for the entire zkSync ecosystem.\
Users can now pay for gas with any ERC-20 token they hold or enjoy sponsored transactions.\
Developers can easily integrate it with our API.

</details>

<details>

<summary><strong>What is the fee model?</strong></summary>

Zyfi operates two different paymaster contracts: the Sponsored Paymaster and the ERC20 Paymaster.

A 20% markup on gas fees applies to transactions processed through the ERC20 Paymaster.

A 25% markup on gas fees applies to transactions processed through the ERC20 Sponsored Paymaster.

Note: This fee is only on gas fees, not swap fees.

</details>

<details>

<summary><strong>Why is Metamask not supported on mobile?</strong></summary>

Metamask mobile does not support the paymaster flow currently.

</details>

<details>

<summary><strong>What is a paymaster?</strong></summary>

A Paymaster is an account that compensates for the transaction fees of other accounts, allowing for fees to be paid in ERC20 tokens instead of ETH by converting them on the fly. This facilitates users who want to interact with protocols without worrying about having ETH for gas fees, enhancing accessibility and usability within the zkSync ecosystem.

</details>

<details>

<summary><strong>What is ZkSync's native Account Abstraction?</strong></summary>

ZkSync is the first EVM-compatible layer 2 that supports account abstraction at the core protocol level. This enables EOAs to send transactions gaslessly on zkSync through any wallet (Metamask, TrustWallet, Rabby, etc.)

</details>


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