> For the complete documentation index, see [llms.txt](https://ymq-app.gitbook.io/ymq-product-options-app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://ymq-app.gitbook.io/ymq-product-options-app/faq/implementation-principle-of-app-option-price-add-on.md).

# Implementation principle of app option price add-on

### 1. Draft order (default)

<figure><img src="/files/qIRv1CAjB7zGlneQ3f9u" alt=""><figcaption></figcaption></figure>

<figure><img src="/files/L9OVVhh3zEkPovaT3HoP" alt=""><figcaption></figcaption></figure>

### 2. Binding variant principle:&#x20;

Bind option A to variant A. After option A is selected, the bound variant A will also be added to the shopping cart. Please refer to the attached iamge 1

<figure><img src="/files/O0z9211Dz1u89cpmIUvQ" alt=""><figcaption></figcaption></figure>

### 3. The one-cent principle:&#x20;

Create a one-cent variant in shopify. If the add-on price is $100, 10,000 one-cent products will be added at checkout, which is exactly $100.&#x20;

This principle is not open yet, if you need it, please create a one-cent variant in the shopify background, and send me the variant id, and I will set it up for you.

<figure><img src="/files/omu3M8q1APEtrlG87TPG" alt=""><figcaption></figcaption></figure>