1) Security Enhancements
2) RSK (rootstock) support
3) Address Book
https://decentral.zendesk.com/hc/en-us/articles/360001997634-Jaxx-Address-Book-What-is-it-how-it-works-how-to-use-
4) UI Enhancements and minor bug fixes
Choose Download Locations for Jaxx Blockchain Wallet v1.3.15