Such companies offer a wide variety of unmoderated matchmaking services, most of which are profile-based.
Online dating services also differ widely in their revenue streams.
As a contributor to Tom's Guide he's found a happy middle ground writing about apps, mobile gaming and other geekery.
You can post your profile, use advanced search, send and receive messages absolutely free.
Some sites are completely free and depend on advertising for revenue.
Others utilize the freemium revenue model, offering free registration and use, with optional, paid, premium services.