Celo

Celo focuses on payment applications and experiences accessible from mobile devices. Its current architecture is an Ethereum layer 2 based on OP Stack. Integration specifications should use that architecture rather than carrying over assumptions from its former layer 1 design without review.

Product value depends on the combination of EVM contracts, available assets and user journeys. Selection should cover how users acquire the payment asset, transaction fees and the exit route needed by the recipient. A mobile focus alone does not establish whether that complete journey is supported.

Celo separates EVM-compatible execution, EigenDA data availability and settlement on Ethereum. Protocol contracts provide additional functions, including management of supported fee currencies.

Wallets and application clients need to construct transactions compatible with those functions. Displaying a stablecoin balance does not establish that it can pay gas. Tests should check the accepted currency, configuration and behaviour when a user lacks funds or switches networks. These conditions belong in both transaction construction and the interface’s guidance before the user signs.

The fee currency is part of transaction configuration and depends on currencies supported by the network. Integrations need to estimate costs for that mode and verify RPC and wallet support. Gas sponsorship, when used, additionally introduces its own funding budget and authorisation rules.

Celo can fit payment applications prioritizing usability while requiring Solidity contracts. Its fee options are relevant where users should operate mainly with one asset instead of routinely managing several balances.

At Metlabs, we test collection, sending and reconciliation using the product’s intended wallet. We also examine entry and exit services available to the target audience. Improvements should be demonstrated across that journey rather than inferred from the network’s mobile positioning. The result determines whether the integration simplifies the experience enough to justify its specific handling.

For remittance or collection applications, test what happens when a recipient receives an asset but cannot complete the next step. Reconcile refunds and pending payments while distinguishing contract results from on-ramp or off-ramp outcomes. Mobile testing should include intermittent connectivity and session recovery so a delayed display does not encourage a second payment.

Alternative fee currencies introduce compatibility requirements for each wallet and tool. The L2 architecture also adds sequencing, data-availability and bridge dependencies, separate from application-contract security.

Stellar can be an alternative for payments based on native operations, while other layer 2 networks may better fit particular EVM dependencies. Compare access to assets and services as well as fees. Choosing Celo does not automatically complete a banking entry or exit route; those external processes still require their own integration and operational support.