If your product comes in multiple versions, like different sizes or colors, you can use the Variants feature. You add up to 3 options with up to 100 values in each option. You can track quantity (stock) for each variant individually.
When you create an invoice, you can add variants by entering the name (it appears in the search list) or by browsing Products and selecting a product (a list of all variants for that product appear).
MOBILE APP
Click on More and select Products
Click on + to add a new product
Enter Name, Description and Price
Scroll down to Variants and click on Add variants
Add an option (e.g. Size, Color, etc.) and click Next
Add values (e.g. L, XL, XXL or Red, Green, Blue...) and click Save
If you need more options with values, you can add new ones
An example with three options and ten values...
...and the final result with all option/value combinations.
You can now edit any variant you like, change price, tax, SKU, turn on quantity tracking or weight.
You can also add a new variant manually
WEBSITE
Navigate to Service/Products and create a New product
Enter Name, Description and Price
Scroll down to Variants and enable it
Add up to three options (e.g. Size, Color, etc.)
To each option add values (e.g. L, XL, XXL or Red, Green, Blue...) separated by a comma
Save the product
A table with all variants with prices, SKUs and inventory level appears
You can also add a new variant manually by clicking on +Add variant