A sub-collection is a collection inside another collection. To create a sub-collection, open a collection and tap on the button (top-right corner).
![Sub-collection menu](/img/screen/collection-edit-menu.png)
![](/img/iphone-14-pro.png)
Select Edit in the contextual menu.
![Sub-collection menu](/img/screen/subcollection-menu.png)
![](/img/iphone-14-pro.png)
Then select Sub-collection in the new menu.
![New sub-collection](/img/screen/new-subcollection.png)
![](/img/iphone-14-pro.png)
Choose a name and then tap on Next.