Yes! - You can import a CSV spreadsheet to Leader easily (**available on Leader Android, for iOS & Web this is coming soon).
Note: If you have an Excel spreadsheet, first open Excel and save the file as CSV.
Steps to import the CSV file:
Open Pipeline tab (first tab) or the Labels tab.
Tap on the 3 dots in the column you would like to import the CSV file.
Select Import from CSV
Choose the CSV file, and follow the steps on the screen for matching the fields in the CSV file to the fields in your Leader contacts.