The best alternative is OkCupid, which is free. Other great apps like Plenty of Fish (POF) are Alovoa (Free, Open Source), Tinder (Freemium), Badoo (Freemium) and Feeld (Freemium).
Does Plenty of Fish have matches?
Searching for matches is one of the essential parts of online dating. On Plenty of Fish, you can search matches according to several distinct sets of criteria. You can look for people by their age, education, location, and everything else you might think its important.
On July 14, 2015, Plenty of Fish was sold for $575 million to Match Group (owner of Match.com, OKCupid, Tinder and Hinge, based in Dallas, Texas). The headquarters remain in Vancouver and have recently been expanded.