Branchable's web server was vulnerable to the heartbleed openssl vulnerability. It's possible that https private keys could have been leaked to attackers.
We've upgraded Branchable, closing the security hole. However, to regain security, any https certificates need to be regenerated, and the old keys revoked. We're working to do that for Branchable's own https certificate.
Branchable users who installed their own https certificate should consider updating it too.
Update: Branchable's SSL certificate has been replaced. We have pre-emptively closed all existing login sessions to all Branchable sites, in order to guard against session hijacking. It is now safe to log back in.