Although Twitter has changed how characters are accounted for, the 140-character limit is still enforced, and it is not possible to post longer tweets.
Or is it?
Infinitweet now lets you post tweets without character limit, and even allows you to choose format your posts in terms of colors, fonts, sizes and alignment.
Infinitweet is available for iOS, watchOS, Android and Google Chrome, either as a free or pro version.
Happy (long form) tweeting.