Steemit.com is just one platform of many where you can earn STEEM.
Here are the others so far and this list will grow:
Busy.org - Facebook like design for Steem
Mspsteem.com - MSP Front End for Steem
Steem.kr - Korean front end for Steem
Esteem - Mobile Steem Client for iOS and Android
SteemitStage.com - SteemitInc Mirror of Steemit (for testing out new features. Often works when steemit doesn't)
condenser.steemliberator.com
dApps - These decentralized applications serve a variety of purposes, built on top of the Steem Blockchain:
Utopian.io - For rewarding Open Source Developers via the Steem Blockchain.
Chainbb.com - a Forum structured interface for Steem
SteepShot - An instagram like client for Steem
Dlive.io - Live Video Streaming platform for steem
D.tube - Video Platform like Youtube with Steem rewards
Dsound.audio - Soundcloud like Platform With Steem Rewards
Dmania.lol - An app for posting your favorite memes, funny pictures, gifs and videos.
Zappl.com - A twitter/reddit mash-up, meant for short/quick sharing of media and links.
Appics.com - a revolutionary social mobile APP that lets anyone without prior crypto-knowledge benefit from blockchain technology effortlessly. (Coming Soon, of the first SMT created)
Passagex.com - Event-Ticketing Network - Being built on the Steem Blockchain
Oneplace.media - A different way to view Steem Posts (it looks nice over there :)
Source:
https://steemit.com/steemdev/@inquiringtimes/steem-web-resources-tools-apps-communities-ect