Using the Add button above the list of individuals, you can start adding an individual that is initially not related to others, but in that dialog you can add an individual and then add relatives directly.
The add dialog is a quick way to get initial information about an individual including their sex, date of birth and death, place of birth and death as well as general name information. There is a also a free form date of birth and death, so if dates are not exact basic text can be added.
You can swipe left on your added rows to choose to add another (unrelated) individual, as well as adding parents, spouse and children. You can also drag and drop to relate individuals.
As long as individuals have a first and last name, they can be saved. If any individuals are missing either of these, you’ll be prompted if you want to save others (but it will not save those missing a first or last name, or any of their descendants)