CSV (Comma Separated Values)
This file format allows for a data table to be easily retrieved into a variety of applications. However, it is best viewed within one that allows easy manipulation of data such as spreadsheets and databases that come in columnar format (Excel, Numbers, OpenOffice, etc.) None of these application types has the facility to easily format the width of the data columns, and quite a bit of manual reformatting will be required to properly view the data.
The downloaded CSV file also omits certain data, including: contact pictures, the "nickname" field, the "AIM" field, "website" field, and sometimes the "notes" field. Additionally, special characters and foreign alphabets aren’t supported and the "call" field is limited to four phone numbers regardless of their classification as "mobile," "work," "home," etc. These labels are also sometimes lost. This is not specific to Lookout; a file exported from Microsoft Outlook also omits this data.
vCard or electronic business cards
Microsoft Outlook supports the vCard, as does the Mac Address Book application, and online contact management sites such as Google Contacts. The downloaded vCard file omits contact pictures, the "nickname" field, the "AIM" field, and the "website" field. It seems to have no limit on "call" field phone numbers, and it does support many (but not all) special characters and foreign alphabets. The vCard format requires less reformatting of data then CSV.
Note: For Contacts, the downloaded file can also be opened using either a text editor (Notepad, TextEdit, etc.), word-processing application, or a specific program.