If you're interested in cutting edge Construct features try the Beta releases. These releases should not be used unless you are willing to tolerate some bugs.
Facebook Instant Games support & lots of bug fixes
Hotfix for r90
Lots of fixes and changes, and new in-progress Ukrainian translation
A few more bug fixes before stable release
Fix for saving issue in r88
Beta opt-in; Spanish & Czech languages; lots of additions and fixes
Project saving/opening improvements; some additions and fixes
Bug fixes; new in-progress Dutch translation
Desktop build improvements & a few more fixes
Some last fixes before a stable update