Houseparty - Brining empathy to online communication.
Privatter - Privatter is the easy way to share long texts and pictures set limit on your followers. You can post them by Sign in with Twitter account to this site.
Booyah - Video chat with up to 12 friends at the same time.
Twishort - Twishort is a best Twitter app for writing longer tweets. Tweet more than 140 characters
Slack - A messaging app for teams who see through the Earth!
5Tweets.com - Type a long tweet and 5Tweets will rewrite it into multiple tweets with a tweet count.