> ## Documentation Index
> Fetch the complete documentation index at: https://docs.mattildapayments.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Android options

The SDK can be configured in a few ways.

| Field                     | Optional / Required | Description                                                                                                                                                                                                                                                                                                                               |
| ------------------------- | ------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `gr4vyId`                 | **Required**        | Should always be set to '"mattilda"'. The ID automatically sets the `apiHost` to `api.mattildapayments.com` for production and `api.sandbox.mattildapayments.com` and to `embed.sandbox.mattildapayments.com` for the sandbox environment.                                                                                                |
| `environment`             | `Optional`          | `"sandbox"`, `"production"`. Defaults to `"production"`.                                                                                                                                                                                                                                                                                  |
| `token`                   | **Required**        | The server-side generated JWT token used to authenticate any of the API calls.                                                                                                                                                                                                                                                            |
| `amount`                  | **Required**        | The amount to authorize or capture in the specified `currency` only.                                                                                                                                                                                                                                                                      |
| `currency`                | **Required**        | A valid, active, 3-character `ISO 4217` currency code to authorize or capture the `amount` for.                                                                                                                                                                                                                                           |
| `country`                 | **Required**        | A valid `ISO 3166` country code.                                                                                                                                                                                                                                                                                                          |
| `buyerId`                 | `Optional`          | The buyer ID for this transaction. The transaction will automatically be associated with a buyer with that ID.                                                                                                                                                                                                                            |
| `buyerExternalIdentifier` | `Optional`          | An optional external ID for a Gr4vy buyer. The transaction will automatically be associated with a buyer with that external ID. If no buyer with this external ID exists then it will be ignored. This option is ignored if the `buyerId` is provided.                                                                                    |
| `externalIdentifier`      | `Optional`          | An optional external identifier that can be supplied. This will automatically be associated with any resource created by mattilda Pay and can subsequently be used to find a resource by that ID.                                                                                                                                         |
| `store`                   | `Optional`          | `'ask'`, `'preselect'`, `true`, `false` - Explicitly store the payment method, ask the buyer or preselect it by default. Requires `buyerId` or `buyerExternalIdentifier`.                                                                                                                                                                 |
| `display`                 | `Optional`          | `all`, `addOnly`, `storedOnly`, `supportsTokenization` - Filters the payment methods to show stored methods only, new payment methods only or methods that support tokenization.                                                                                                                                                          |
| `intent`                  | `Optional`          | `authorize`, `preferAuthorize`, `capture` - Defines the intent of this API call. This determines the desired initial state of the transaction. When used, `preferAuthorize` automatically switches to `capture` if the selected payment method doesn't support delayed capture.                                                           |
| `metadata`                | `Optional`          | An optional dictionary of keys and values for transaction metadata. All values should be a string.                                                                                                                                                                                                                                        |
| `paymentSource`           | `Optional`          | `installment`, `recurring` - Can be used to signal that Embed is used to capture the first transaction for a subscription or an installment. When used, `store` is implied to be `true` and `display` is implied to be `supportsTokenization`. This means that payment options that do not support tokenization are automatically hidden. |
| `cartItems`               | `Optional`          | An optional array of cart item objects, each object must define a `name`, `quantity`, and `unitAmount`.                                                                                                                                                                                                                                   |
| `theme`                   | `Optional`          | Theme customization options. See [Theming](https://github.com/gr4vy/gr4vy-embed/tree/main/packages/embed#theming). The iOS SDK also contains an additional two properties within the `colors` object; `headerBackground` and `headerText`. These are used for the navigation background and foreground colors.                            |
| `locale`                  | `Optional`          | An optional locale, consists of an `ISO 639 Language Code` followed by an optional `ISO 3166 Country Code`, e.g. `en`, `en-gb` or `pt-br`.                                                                                                                                                                                                |
| `requireSecurityCode`     | `Optional`          | An optional boolean that forces security code to be prompted for stored card payments.                                                                                                                                                                                                                                                    |
| `shippingDetailsId`       | `Optional`          | An optional unique identifier of a set of shipping details stored for the buyer.                                                                                                                                                                                                                                                          |